The concept of having the driver choose the storage amount when charging is absolutely phenomenal! I applaud whomever came up with this idea, especially because it will significantly increase the usable lifespan of the battery pack. Thanks for sharing this neat insight into the world of Li-ions in general, and thanks for continuing to update this blog.

Your battery pack is almost certainly 99 cells in series by 69 parallel strings - it’s really the only way to make the numbers work out. If you factor 6831 you get 3 x 3 x 3 x 11 x 23, which prettty much tells you how it was designed alongside the 375 nominal volts figure. The total voltage, one infers, is 3.8 volts per cell, which is plausible for “just off the charger” numbers. And the lifetime-increasing effects of limiting your max charging to 4.15 volts makes sense to me.

Here’s the part I don’t get. To justify a 50 kWh battery pack energy, and a 200 kW peak power, you need to have batteries rated for 4C discharge. You can calculate this for anyone’s EV design by dividing the maximum power by the total energy. If the voltage is a nominal 375 for the pack the capacity of each cell has to be about 1950 mAh per cell. That’s a good “real world” figure for a nominal 2000 mAh cell. And it’s consistent with the small capacity de-rating you point out due to the reduction in charging voltage.

I don’t see a battery like that on the market anywhere outside of Lithium Polymer cells. The 18650 cells I can find in the 2000 mAh class are rated for no more than 1.5C-2.0C discharge.

So how do you get away with discharge rates of up to 4C from batteries that are lifetime-managed, and also of high energy density, and also affordable? I’m really curious as to this point? Whose cell are you using?

Is it similar to loss of gas mileage over time in a combustion automobile? So, after 5 years we give it a “tune-up” (new battery pack). How much do you anticipate a new battery pack would be (just a guesstimate would work)?

Have you been looking at Altairnano’s Nanosafe battery technology as a future upgrade?
They claim greater cycle life, (15,000+), 20+ year calendar life, 10 min charging time, no thermal runaway, greater operating temperature range, no need for heating or cooling, etc. Basically the miracle battery we’ve been waiting for. Phoenix motors is using them in their new SUV/SUT.
Altairnano.com

—

Editor’s comment: Tesla Motors makes it a point to stay on top of emerging technologies. Also, check out Martin’s Balance blog.

Hi,

I read in an article that Tesla is going to license the battery technology. Great! All that engineering shouldn’t go to waste. Any chance you’d sell a battery system for use in a hobby EV conversion? The EV hobbiest conversion market is there, and growing.

The article is here:

autobloggreen.com

You can get away with discharging an 18650 cell at 4C if you only do it for a few seconds. The real limitation is thermal, so if you sence the battery temperature and limit discharge rate if it gets to hot you will be fine. My guess is the only time you could discharge at 4C long enough to overheat the batteries is if you entered the Pike’s Peak race. Then again the Tesla cooling system may even allow that.

Mr. Martin Eberhart. Thanks for the extra information about the batteries you are currently using in the Tesla roadster. As an electrical engineer, I think the biggest brakethrough you have made is the incredible power density of your squirrel cage, 3 phase, 248 hp electric motor made by AC Propultion (70 lbs for the motor, ~160 lbs for the motor, differential and transmission).
I just read an article about the batteries made by Altair (Nanosafe). They are currently building a 35 KW*hr for an electric SUV with a range of about 130 miles. I have done calculations on both your batteries and those made by Altair and I found that your batteries have a slightly higher energy density. However, Altair is making a claim that after extensive torture tests they have recorded 15,000 full charge/discharge cycles and that their batteries have power densities of 4000 W/Kg (A123 Systems batteries provide 3000 W/Kg but they only last 2,000 full charge/discharge cycles). Both Altair and A123 system batteries have an internal resistance of only 10 mili Ohms.
It is no secret that to increase power density in a battery you just have to find a clever way to increase the surface area used by the electrodes (as long as everything else is kept at the same conditions). I believe it’s just a matter of time to have cells with internal resistances of less than 4 mili Ohms (which will increase the power density to about 10,000 W/Kg). Also, as you can see, the lower the internal resistance, the lower the (I)^2*R losses and therefore the less relevant the complex cooling system becomes.
I would like to know if you would be willing to have Altair and/or A123 system build you a battery pack with the same dimensions so that you can just “swap” batteries and then evaluate if there is any improvement in performance.
My second question is: Can you scale up the electric motor to twice the power and twice the mass (496 hp, 140 lbs) twice the torque and skip the transmission altogether?

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Editor’s Surprise: The motor in the Tesla Roadster is not made by AC Propulsion. We designed the motor. We made the motor. See the Motor City blog for all the details. 

I keep a Tesla picture on my computer at work and get nuerous comments and willing ears to hear what this car is but I had one engineer (by title not knowledge) when he heard it was electric it was immediately no good did not want to hear anymore but everything he touches is botched up. Those batteries are what I expected in size this is a case of EXCELLENT research and work. I want to do a side by side analysis of the LiOn and the Altairnano batteries. I have several thoughts in mind a EV Tesla ,Phoeinx or modify an ICE car to EV. One other thought is PHEV my 2004 Prius with LiOn Maybe have two cars also. PS I have a PhD in engineering with heavy electrical background.

Just saw Telsa Roadsters & Martin Eberhard on PBS ‘ Nightly Business Report. Word is out on the (Wall) street now! Tesla should definitely build its sports sedan plant on the outskirts of somewhere, off the elect. & other utility grids and where land is dirt cheap. They could afford more land and have a real spacious, landscaped “campus” type facility-could be spectacular, as auto plants go-nothing like it anywhere. They might also go for “economy of scale” and build an industrial park campus & make money on rent as well. A small well-fed pond (or lake) would be nice, serving the bldg. (or bldgs.) fire sprinkler system as well. With Nanosolar & ( similar) supposedly coming out in 2007, the timing is perfect for a 100% “green” plant (but of course).The installation cost would be cost effective & the ongoing utility savings would be big (obviously).All sorts of green building components have come out in recent years,with more on the way. Should be some fed./state tax breaks for a pure green bldg. too-to go with whatever state incentives are offered to build there. Also, employees could probably live in cheaper outlying “country” housing-away from city commute. If I were part of a state development agency, I’d pull out all stops to get Tesla to move there-it would have great PR value-and then there’s the future ” phase 3 family sedan” plant to consider. Gov. Arnie will be making a mistake if Calif. doesn’t match other state incentives.

Thanks, I really appreciate the info in these blogs. I have to say that as physicist, electrical engineer and a car enthusiast, I am triply excited about the Tesla Roadster. I’ve been following it in the media and have even had the privilege to see it in person. I wish your new company the best of luck and much success.

Could you guys talk a bit about the transmission? I heard that the one you’re using in the prototypes is giving you problems and you’ve decided to make a change. (In fact in a Today show test drive vid it broke!video.msn.com) Any details about that? Will this change cause any delay to the projected delivery date of the first consumer vehicles?

Are the brakes standard vacuum assisted hydraulic brakes (i.e. including a master cylinder and brake lines with DOT4 fluid or whatever)? Do you then have an electrical vacuum pump running under the hood, since there’s no engine vacuum in this case? Out of curiosity, I had asked one of the Tesla people this question at an EV car show at Palo Alto High School a while back, but she didn’t seem to know how brakes worked in a normal car. Not her fault, though, I think she was more involved with the motor or something.

Thanks again!! By the way, if you want to donate one of your cars to us guys here at Stanford, just let me know. I’m sure we could run some “tests” for you.

Is the 95% max charge also used to allow a small amount of headroom if a fully charged vehicle drives straight out of the garage and down a steep hill - using regen braking as it goes? (It could happen in San Francisco)

This is a great company and a great car. I have been very cynical about electric cars for a long time, but you guys have pulled off some amazing feats!

I had a question regarding the power/torque curve vs. charge. I have found with battery-powered remote control cars, they ran very fast with a full charge, but slowed down considerably as the charge was exhausted. Does your power curve degrade at all as the the battery pack is discharged? Is there a loss of power with an older (but still within its design life) battery pack?

Embassy,

Re: Battery configuration. This article on Electronic Design sheds some light:

www.elecdesign.com/Articles/Index.cfm?AD=1&ArticleID=14108

I notice you didn’t post the answer to - How much will it cost to replace the battery pack? Include estimated shop costs if you care to answer me. At the same time I would imagine that there would be advances in battery technology in what (?) 5 years times. I notice you are going the DeLorean route in order to get in the auto manufacturing business, is that just the best bet to overcome the entry level hurdle? Do you have plans to make cars that regular people can drive? I ask because at times, I have been a professional auto mechanic - Ask any auto mechanic if vehicles are designed to be worked on ? Go to the next room to listen to the laughter at an an acceptable volume. I have fixed my washer and dryer over the years and been amazed to find out , they are actually designed to be repaired quickly . Do your designers consider this? - A thought for the long term (yes I know Keynes said, “IN the long term we are all dead . ” ) Time will tell.
Gepay

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Editor’s Answer: Battery prices are dropping and energy density is rising. When we are ready to offer battery pack replacements, they will have a price.

Take a look at our Secret Master Plan to understand a little more about our business plan.

All good design allows for serviceability. We have good design.

Re: Mark Looper’s statement –

The reason this batch of cars coming out in the next few years have a greater range is not only to help commuters and travelers have an ability to go a good distance without a recharge, but also to prove that electric vehicles are competent alternatives for the masses. It’s unfortunately a burden of proof that a new technology must be very capable, or people will shun it. The EVs that came out in the 1990s had the range more of what you’re talking of, and were ripped apart by skeptics because of it. It’s true that most of us will rarely need such a long range, but right now, the task is to show it is possible. Plus, with lots of r & d and company brand-building, they will come out with vehicles that target individuals that have deeper pockets until it is possible for the price to come down. I think you would find that if GM had sold the EV-1 (and if they had actually shown an interest in doing so) it would have likely had to cost around the price that the entry-level White Star sedan will cost (~$50-55k). Even Phoenix Motors SUT which is based on a very inexpensive Ssangyong (Korean car company) platform is estimated to sell to fleet at $45,000, and even then they will only be making a profit because of the California ZEV manufacturing credit. Essentially without making hundreds of thousands of units, price to make things are higher, and to be able to sell hundreds of thousands of units, you need people to have confidence in your product from the mainstream public. This is why the higher-end models are coming first.

GM says they spent over a billion dollars on an electric car and only could lease several hundered. Tesla sells out one year of production of a six figure roadster ev in four months. Hmm, seems like ev’s might have been a more prudent technology for GM’s bottom line and we all could have had the opportunity to be driving that family ev right now. I bet any money when battery technology continues to get better and better like Tesla has clearly exploited greatly, unlike large automobile companies have. Batteries will not be an issue for automotive applications. Maybe Kirk could drop a few buck over to Tesla’s way and speed this process up

saving in mn

Is there a timer on the charging unit? Say I get home from work at 6pm, park the car in the garage and plug it into the charger. However, I don’t want the car to actually start charging till around 1am when the electricity rates lower. Can I set the charger to do that sort of thing automatically?

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Editor’s Answer: The timer is set via the VDS (Vehicle Display System).

If the Whitestar is rear wheel drive like the autoblog article states what about some type of All Wheel Drive vehicle as many of us need some type of AWD in the winter time. My street alone does not get plowed properly. I helped push a few rear wheel drive on it already.

First of all, the term “corporate welfare” implies that the government is somehow giving money to Tesla Motors. Sorry, but I don’t consider it “welfare” when the government chooses to confisgate money from a corporation at a slightly lower rate than they do from other corporations.

Secondly, you are not looking at this from a long term perspective. This is an investment. The calculation is that the tax breaks offered now will pay dividends for the state in the future as the company grows and employs more taxpaying workers. This is how capitalism works. If the state wants the benefit of future revenues, they should bear some of the risk. Obviously, other states think its a good investment.

Tesla:
At the editor’s kind suggestion, I read again the battery safety white paper after my post above. My apologies for being a bit unclear. I think the safety features explained in the white paper are superlative. It sounds like triple redundancy safety of the ESS! Fantastic! The flaming reference I made was intended with respect to a ruptured gas tank of a conventional auto. Sorry. Mechanically, I would like to know at what point the simulations predict the ESS breaks loose and crashes into the passengers in a headon incident, as a solid mass. What is the safety margin there?
While I’m at it, have the reliability engineers come up with a MTBF calculation for the 13,000 -plus battery connections? Can that be shared?
Thanks.

It is not corporate welfare for cities to offer preferential tax deals, yes tax breaks, to entice corporate investment in the area. Tesla or any other company desires to be as competitive as possible in the marketplace and they have a right to go to the city that offers them the best deal. If cities do not desire their factory, then they are under no obligation to offer any special treatment. For those that choose to compete for Tesla’s investment, they must believe the amount of money being brought to their city is greater than they are spending. They are getting no taxes from Tesla currently. Even If the city offers a corporation the opportunity to pay very little taxes, that is still better than the zero they now collect. Not to mention the jobs, which all the employees will pay local income and sales tax on. If the cities did not believe it was in their interest to offer the corporate enticements you mistakenly call “corporate welfare,” then they would not do it. Tesla and every other company has every right to go where they are offered the best opportunity. To do any less would be to compromise their position in the market.

SRB - thanks for the link. Doesn’t answer the 4C vs. 2C discharge question but clues me up on a lot of other stuff.

“AltairNano batteries” :
Looks nice for heavy pacs, exelent safety (up to +75ºC working temp), and a great cykle life.

Only one problem if you would like to use them in a tesla! (and maby also the price?)
they are under 100Wh/kg….

so..
You Get slow (double? the weight to get the same range)
Or short (on the same battery weight)

/ J

Article from Power Electronics magazine from February this year:-

powerelectronics.com/mag/602PET06.pdf

Which looks at the application of Li-ion batteries in portable power tools. Discharge rates of up to 10C are discussed and the effect this has on capacity.

Let’s assume that you hammered these cells at 10C (more than double what would be needed to either accelerate the Tesla at maximum torque or maintain it at its top speed). At this discharge rate the capacity (for the Sony 18650 VT mentioned in the article) would be around 1.03 Ah as opposed to slightly better at 1C or less. (Rated capacities are always more pessimistic)

Tesla cells are 2.2 Ah (no idea who makes them but take your pick between Sony and Sanyo). Let’s assume that 10C discharge gives the same 5% hit on capacity leaving 2.1 Ah

The cells are charged and discharged between 4.15 V and 3V. So that’s an average of 3.575 V. (Which is where the “3.6V nominal” value quoted in a previous post comes from). Using the 2.1 Ah figure from above, each cell can provide 7.5 Wh of Energy. 6831 cells would give 51.2 kWh. Which is fine for capacity and therefore maximum range at sensible speeds.

10C discharge means 10 times the discharge rate implied from the capacity value. 2.1 Ah means you can draw 2.1 A for an hour. 10C means you can draw 10 x 2.1 = 21 A, but of course only for 6 minutes (a tenth of the time). In practice this current would be shared between parallel arrays of batteries. If there were 69 of them, each array would only need to produce 0.3 A. This is where the lower C values come from. Arranging batteries in parallel allows you to reduce discharge rates for individual cells.

But let’s be incredibly silly and imagine that each cell has to deliver 21 A. Total current would be 69 x 21 = 1.45 kA !!. Let’s take the nominal ESS p.d of 375 V. This would give us a total power delivery of over 0.5 MW! Of course there is no suitable wiring harness or electric motor or transmission system or tires that could handle that and remain anything resembling a normal sports-car, either before or after the fireball! But on paper it does give you an acceleration approaching 3G. Within about 15 seconds you would pass the sound barrier.

Getting back to the real car….

Cells could be arranged end to end in rows of nine cells per row. Each row would lie along the axis of travel of the car. Each row is electrically connected in series to the row above. 11 rows on top of each other would contain 99 batteries and give a total P.d which varies from 410 V at full charge, down to 297 V at cut-off. This gives me an average value of about 354 V (not the same as the 375V value quoted in the ESS White Paper). Each of these 11 rows could be called a “panel”. There would have to be 69 of these panels arranged side by side across the width of the car. Adjacent rows in each panel could be separated by a system of 10 cooling sheets which run horizontally across the ESS. The other obvious fault with this model is that it doesn’t account for the 32.4V value quoted in an earlier post.

The article goes on with:-

Last year, Valence Technology (www.
www.valence.com) targeted power tool applications
when it introduced its Power Cell in an
18650 cylindrical format. Like other Li-ion
batteries offered by the company, the Power
Cell employs the Saphion chemistry, which
incorporates phosphate-based cathodes
rather than cobalt-oxide. The phosphatebased
cathodes offer greater safety and
less susceptibility to thermal runaway than
cobalt oxide.
The Power Cell offers nearly a 1.1 Ah of
capacity at a 10C rate but can deliver higher
current pulses.[3] For instance, the cell can
supply a 30-A pulse for 30 sec.

Current cell designs seem to offer more than enough power density. It’s the accumulated effects that both temperature and energy/power transfer (to and from the cell) have on the energy density that is the crucial area for research.

By the way, does your electric motor have rotation sensors or is it sensorless?

Embassy. Is the greater capacity of 2.2 Ah simply a result of a larger discharge potential? e.g 1030 mAh for a discharge of 4.1V to 3.76V - a drop of only 0.34V. 4.15V to 3V is more than 3 times the amount. Of course, there won’t be a linear relationship between pd and capacity but maybe the 4C rate you’re looking for just a modification of existing 1Ah/4C cell chemistry to accommodate the lower discharge stopping point of 3V?

david_42, I was not whining…and SRB’s post didn’t appear until after I posted. That article on the ESS config is exactly what I was looking for. There is a lively discussion going on over at the teslamotorsclub forum regarding the configuration of the ESS and this info has helped tremendously. The only question that remains is, as Embassy has mentioned, how they get large discharge C rates out of cells that have 2.2Ah capacities.

#Not true, Dean, they do exist…

well, something may exist on the drawing boards, laboratory desks and roadmaps but that is not the same thing as existance in shops or commercial availability.

tesla roadster was in developement for 3-4 years. altairnano tesied their batteries in previous month. a whole new car with whole new drivetrain in less tihen half a year? sure..

Comment about batteries concern of Jonas

Tesla Motors claimed 250 miles range for EPA testing standards. I took out all the data they presented on the site and created a model taking into account rolling resistance, aerodynamic drag, battery capacity etc. My model indicated the following:

1. Largest range would be 350 to 370 miles but at the speed 25 to 30 mph consuming sustained electric power of 4 kW
2. Claimed range of 250 miles would be provided at a speed 50 to 55 miles consuming sustained electric power 10 to 12 kW
3. More “realistic” range of 200 miles ones mentioned by Martin Eberhard would be provided between 60 and 65 mph speed with sustained power 15 to 18 kW
4. At speeds 75 to 80 mph the range degrades to 140-150 miles at sustained power 25 to 30 kW assuming no degradation in battery capacity for higher power discharge.
5. Top speed of 130 mph correspond to about 105 kW power matching presented torque-power curve data etc. But range at this speed would be barely 60 miles.

From this data I could say that question of high discharge rate is not applicable because sustained discharge for claimed 200 - 250 miles range corresponds to 10 - 15 kW power. Here you discharge corresponds to 5 hours ( 0.2 C rate if I understand 1 C meaning as 1 hour discharge correctly ). Surely you have to accelerate and decelerate. But for the 2C discharge rate it means 100 kW power. At this power you would make speed changes in 10 sec time frame for anything you doing between 0 - 70 mph. Statistically this would cover 95 % of driving I guess for most of the people. So you can get away with 2 C batteries only.

Sure if anybody would drive the roadster with maximum acceleration all the time and frequently come to 80 - 90 mph speeds and back to standing still or driving 20 mph etc battery pack will degrade much sooner than 100 to 125 K miles claim. Range under this conditions would also be less than 100 miles. But the trick I guess is that such a driving could be done mostly by reckless young people using somebody car they do not own in a “who cares” mode. They are not expected customers. People who pay $100 K for a car typically very rarely would use full acceleration. They would use it just to escape an emergency very rarely. In most cases they would be driving well within 2 C discharge limit.

I guess Tesla Motors people are a bit reluctant to discuss range and performance degradation of their car under very stressful conditions. What they built appears to be not the match for “racing” cars but instead a far more practical car bread for easy gaps filling in a heavy traffic rolling typically below 65 mph on today freeways of Bay Area. This car appear very good match for every day commute of highly populated areas. It does not appear good at all for say long freeway road trips through areas with relative wilderness or rural areas. For such trips it would suffer with severe range reduction below 150 miles or lower especially for typical traffic speed of 80 - 90 mph I have observed on such freeways. It either does not appear good for any racing on roads (forbidden by law by the way). But Tesla Roadter do not position the car for this use model at all as they explained. They apparently want to cover every day commute of wealthy people in populated urban areas. For such a commute high acceleration, high regenerative deseleration and reasonable range for 50 - 60 mph speeds is the key and they seems have it. I think most of current customers of the roadster already managed similar research and understood all what I explained pretty well - one would do it for $100 K upfront reservation.

For me personally whatever Tesla Motors company would build I am not a customer simply because I am living in apartment so I never would be able to charge EV realistically at home as they require because I have no home. I just like new technology so it was fun to manage comprehensive understanding of what Tesla Roadster have designed from bits of information they scatter occasionaly.

I have been following this blog now for a couple of months regularly - I would even venture to say that I have read every single posting since the very begining. What I have come to notice is that not a day goes by without someone “discovering” A123 Systems or Altairnano and believing that it is the solution to all of Tesla’s problems. What surprises me even more is when I see names I recognize as regular posters making similar references as if it was something that Tesla did not already get an earfull about the same from the last “discoverer” of Altairnano.
In light of all this, and in light of the fact that , yes, I did read Martin’s well written blog on “Balance” where he explicitly mentions A123 Systems by name and Altairnano in spirit, I would like to point out my own assumptions on the issue. I will first note that Tesla is using a 2.2 ah battery when they can just as easily use a 2.6 ah battery with the same voltage. This means that Tesla is delibirately not using the state of the art, but is using technology with almost 20% less energy density (50 miles of range) for purely economical reasons. Depending on who you ask, the difference in cost between the 2.2 ah cells and the 2.6 ah cells could be as much as 50%. So getting back to the Altairnano issue. Yes - with everything that I have seen, it does seem that if you built a battery pack out of Altairnano cells you would get very similar range - the loss in energy density can be almost completely made up for in the lack of need for all of the heavy safety features (back of the envelope calculation for all you math geeks - 450 Kg box with 50KWh of energy gives you an effective rate of 90 wh/kg - just about exacly what Altairsafe batteries get). It would seem to me that the issue at hand is purely a cost issue. Does it cost more to build a complex battery pack with coolant and redundant safety measures etc. or does it cost more to purchase the batteries from Altairnano? I think for the moment at least the compex battery pack wins hands down. There is simply no way in the world that Altairnano could possibly come close to the cost of the standard 18650 cells on the market - even if the materials and labor and production were all equal in cost (which they aren’t) based simply on the scale of production… Altairnano isn’t a blip on the screen compared to the big boys when it comes to that.
But to top it all off, we should also look at what benefit Tesla can even get from Altairnano - We already established they wont get any benefit from the inherent safety, as the lack of energy density will require that they add more batteries to eat up the weight savings. There is no benefit to the “quick charging” feature in the Altairnano battery as regardless of how fast the batteries “could” charge, there is no way that you will be able to get the gauge of wire that would be necessary for the delivery of that much juice into a residential home anyway (and to those who believe that the solution will be commercial charging stations read further), and as pointed out in the blog above, “the wire size and availability of very high current outlets limit us much more than the batteries do at this point.” And finaly to the only thing that Altairnano could offer Tesla that would be useful - longer cycle/calendar life. This benefit, while certainly nothing to sneaze at, is not nearly as important as it would look at face value. Bare in mind, battery technology is constantly improving, if it improves at historic rates, in 5 years from now the equivelant battery will cost approximately half the amount, and offer almost 50% better range… What is the great benefit in having a battery that lasts for ever when it will be obsolete in 5-7 years? And commercial opperators will know this, currently with a range of “only 250 miles” someone might think that opperating a commercial recharging station could be a profitable venture - it might not happen all the time, but someone is sure to need to refuel… but who in their right mind will invest in a recharging station if the norm is a 500 mile range? How often will people run out of charge then?
So in conclusion, yes, Altairnano certainly has an atractive technology, which may even be useful in Tesla’s vehicles - and I honestly hope they can scale it and make it even better - but unless the price can be competetive with commodity cells the benefits just really are not that great…

Somehow I get this feeling I will be pointing people to this posting very frequently…

How can you get that many batteries cheap enough. My estimate for your battery pack is somewhere around $600,000 - $900,000 per car?

You must be getting these battery cells for less than $5.00 each,,,,, this sounds way to good to be true.

There has been quite a bit of discussion about the Altair Nano batteries, and I believe Johan had the most important thing to say about them. They are an excellent battery and I’m not going to deny that. However, using an Altair or A123 cell would reduce your range by approximately 30-40% (according to rough calculations). It would allow you to draw a significantly larger current from the pack, and charge faster, but weight would be an issue as drawing that much current requires wiring that can handle it, and when working with currents at the theoretical limits, you get wiring in the ginormous range to use the technical term. Tesla is obviously trying to present a streamlined, unified car for right now, and maybe present more options in the future. If someone wanted a high performance sports car then, perhaps you’d select the Altair or A123 pack, and if you needed the range to go visit your grandmother across the state every month, then you’d pick something like what they’re using or a thin-film when they’re mass produced. That’s my 2 cents.

Dr Houten’s desire for AWD for snow conditions would, admittedly, be nice. However, those of us in the Frozen North fondly remember the VW Beetle, before they all turned into rust buckets, and their legendary ability to navigate unplowed streets around here with snow up to the axels, and beyond, plus icy packed snow , while others were stuck - the secret being weight over the drive wheels. I would think that the 900 pound ESS in the rear of the rear drive roadster would go a long way towards this same effect - ground clearance ignored for the moment. (Front wheel drive ICE vehicles achieve the same effect around here.) As for my rear wheel trucks, I add about 300-400 lbs in the rear, just for winter, and I have never gotten stuck with that. Dunno about mountain driving, of course.

FOr some reason the Phoenixmotor cars SUV highly resembles a Pontiac Aztec. Now if this is true or not I am basing that on looking at a picture and a Aztec. In which case give me a Tesla I owned one and that was one to many GM cars. I just hope Tesla shows up in April at the NY auto show I know several people off this list that want to see one. How about taking orders at the car show. Might sell out to 2009 at that rate.

#Gerard wrote on December 3rd, 2006 at 4:37 am
…

$600-$900K?! what are you smoking? those $5 per cell figures are for retail… Tesla is buying wholesale… VERY wholesale. Just figuring their first run of production - 200X6831=1,366,200 cells - a normal laptop uses 4 cells - so they are buying volume equivelant of 341,550 laptops… that would put them at roughly half the buying power of Apple. Considering what happens when Tesla starts building scale - 20,000 cars would make them the largest battery purchaser in the world by far.

Tesla! Tesla! Tesla! (-sorry!) I love this company. I graduated from Faber College, any chance I could get a job with you?-I’ll do anything.I’m willing to start att the bottom-any crash test dummy openings?

Editor’s surprise: We appreciate a good sense of humor here at Tesla Motors, T.J. Did you catch a showing of “Animal House” over the holiday break?

Dr. H. Van Den Houten: The Phoenix Motorcar is a REBADGED and emptied (ICE Engine removed) Ssanyong Actyon - see for example www.ssangyong.co.za/. It is not a Phoenix Design and definitely no Pontiac. I have seen the shape in ‘real-life’ and it looks pretty good, odd shape but quite attractive. The interior is quite impressive for a Korean brand.

I see that there is still an 8k ‘out-of-service-area’ fee. This seems a bit high considering that it’s unlikely that anyone would actually need any service before it becomes available at more local areas. As you’ve stated, it’s unlikely that service will be needed (at a Tesla service center) until the vehicle has reached 100k miles.

How about either eliminating this servce fee or replacing it with a service fee that is charged at the time that service might be needed? I believe that people might be more inclined to take a chance that service would not be needed rather than pay 8k just for the possibility that it might be needed.

—

Editor’s response: Thanks for the suggestion. You can find out more about our rationale for the “out-of-service-area” fee on the FAQ page. See the “Can I buy a Tesla Roadster if I live outisde of California” question.

Although I recognize that this may not be the best spot to say either, I’d like to say two things:

1) To the Tesla team: I believe that Austin, TX would be a good place for the “next city” the Roadster gets introduced into. If not austin, then some other texas city (such as houston), but I believe the central location of austin would be better. Not only that, but there are a lot of techies here in silicon hills that I’m sure would love to get their hands on one of your cars. As a test, you could try bringing the Roadster to an Austin car show and guage support from there. I think you would be pleasantly surprised by the response.

2) To the blog commentors who give design and engineering suggestions: These guys are experienced. They know what they’re doing. They’re smart. They’ve probably already thought of everything that you are suggesting (except the blatantly foolish ones that no one should ever consider), and unlike you have the expertise to make the right decision. They’ve done their homework and have come to the decisions they made based on careful consideration. Ask for explinations of their though process, but please refrain from showering them with “suggestions” unless you have some clue as to what you’re talking about. From the standpoint of an engineer, I can tell you it is truly annoying.

Oh, and as a PS, I have a “suggestion” for the next roadster: bulletproof glass, carbon nanotube body, retractable rocket launchers, and an autopilot in the form of a blow-up James Bond doll (a la Airplane!).

I few down to LA just to see the Roadster in person. IMO it looked better than the photos suggested: it’s lower and wider than I had expected. Only thing new I learned was the $92k sticker price for the 2008 Roadster.

Tesla has ruined car shows for me; dinasaur power motor cars just aren’t attractive anymore.

Tommy - Waiting for the White Star.

I must agree with Tommy Thorn from a couple posts up. I used to LOVE auto shows, yet at the LA show, I really hated it. I felt like I was getting BSed into thinking that 20 MPG was a good number.

halibut you Tesla!! You made me see the light… 100+ MPG or nothing…

Whats the model after the Whitestar? Well, that ones mine!

Reading the information in the above blog article makes me want to learn more about battery technology. The Tesla Motors website and blog is a great place to read up on electric car technology, and I refer the site to many of my electrical engineering classmates. I also show some of the more impressive statistics and facts to friends and family.

Thanks for being as transparent as possible and providing such interesting information about your amazing new vehicle, and I wish all the best for your business. As soon as I land a job out of school, I am going to set aside some of my salary for a “Tesla Fund” that will pay for either the Roadster or one of your next gen vehicles.

Again, good luck!

Wait! -David’s got a point about (dare I say?:) Altairnano-but in the future an improved ” something nano” could be the way to go for a cheap EV / really high-use car-like fleet/rental or long commute cars . Maybe soon (next 5 years ?) batteries could cost 1/10 of what they do now (like “Nanosolar” is supposed to cost 1/10 of regular solar cells)-then it’s really Hammertime for EV’s -can’t touch this! .The next 5-10 years are gonna be great, in any case!

Ian Clifford of Zenn corrected the earlier statement about EEStor. It’s a 100 lb pack, not 500 lb.

“According to company president Ian Clifford, a ONE* hundred pound EEStor power pack will give the car 100 miles+ range. He is confident that EEStor will pull the wraps of their mysterious “battery” very soon; his exact word was “imminent” and that I could, in fact, hold my breath for their announcement.”
* correction.

Here’s an interesting interview with Clifford discussing EEStor:

stadium.weblogsinc.com/autoblog/autobloggreen/iancliffordatedta.mp3

If this lives up to the hype, it’s a shame that Tesla is locked out of their exclusive agreement. They’re just the type of people who could engineer a voltage regulator and fit it to their A/C induction motor. Let’s see if EEStor can embarass the whole electrical industry.

OK so if everyone was drawing 250kw to quick charge their battery packs…where does this sustainable energy come from? Hydro power? Solar power? tidal?
Could these energies sustain such a huge daily power drain from us consumers for normal use let alone charging millions of car batteries quickly all at once?
Iam not sure….? Nuclear?
someone pls tell me so that i can sleep at night with or without the light on!!!
We got enough copper in the world for each car motor?

— 

Editor’s comment: You might find this recent blog article interesting.

I think we need to look at the Super ~ super ~ mega ~ ultra ~ Super dooper conductor to maximise battery power life cycle [reduce resistance]….all loose 100ibs in body weight [reduce resistance] stop global warming to reduce dynamic wind drag [to reduce resistance]…develop anti matter / gravity equaliser [+/- 100lbs]….[to reduce resistance]

OR just stop traveling….. stay in our villages… hike or push bike…return to the dark ages before the dark ages turn to us!!!!!!
OR populate the moon and bounce around for ages>>>at speed>>> for free!!!!

halibut…. nuclear wins again

Note to the editor:

You frequently reference the faq or other blog entries in circumstances which do not answer the posters inquiry. For example, Michael wrote on December 4th, 2006 at 9:04 am about the out of area service fee and you added:

“Editor’s response: Thanks for the suggestion. You can find out more about our rationale for the “out-of-service-area” fee on the FAQ page. See the “Can I buy a Tesla Roadster if I live outisde of California” question. ”

Yet that entry, at this time, has no information on the rationale for this fee. There is no reason there should be any additional charge, the customer should just be responsible for returning the car to the closest service center as needed.

I think a more honest answer would be it is supply and demand and there is no reason to offer the car outside of those markets since at this time you don’t have enough units to supply even California.

Also, Martins balance blog does not address the a123systems battery. It would be useful to comment on specific technologies because recharge time and cell lifetime are important factors that for some outweigh total capacity. I agree it is all about balance but the question is balance for who? It seems in the future it would be great to give options to customers with regards to the battery tradeoffs and hopefully a clear winner in the next gen options will emmerge in the next few years. I think peoples comments regarding batteries are more about the future (1-2 years) than current production vehicles.

It is great that you provide the blog to interact with the enthusiast community. Thanks,

Pete

—

Editor’s surprise: We’re doing our best to answer all your questions. But we’re not going to be able to answer every inquiry in full, particularly those related to trade secrets and long-term business strategy.

Martin&JB: Thanks for your detailed discussion of battery safety as well as your posted white paper on the subject. One immediate question that comes to mind after reading the white paper is the following: In the event of battery failure during operation, the high voltage is immediately disconnected from the car and the car comes to a stop. Or at least that is what I have intuited from the discussion. It seems obvious that on the highway or in traffic, stopping the car cold could cause more trouble than the flame out of one battery cell. Do you have a work-around? One suggestion might be to disconnect half of the ESS from the system while using the other half to limp to the road shoulder. Or perhaps a backup battery for that purpose. Please keep up your great work. You are doing good.

Wow-the Flabby post dovetails perfectly with the David post. First there was the industrial revolution (draft Gore ‘08), then the electrical revolution, tech /computer revolution (draft Gore), dot com evolution- now we’re at the start of the (draft Gore) Green Revolution. This could/should be big-very big (the bigger the -draft Gore- better)!

I logged into CNET to search the status of the search of Jame Kim (editor at CNET) who is still missing in the oregon wilderness but his wife and two kids were rescued. Sadly before watching a video of his search status CNET ran an ad for this car. The ad was probably run randomly but thought it was in poor taste.

Editor’s comment: We are not yet advertising on Cnet or other venues. But we share your concern for James Kim and hope for his safe return.

T.J. I will agree that the fat cats like GM and Ford have a LOT of baggage and overhead that Tesla doesn’t have to deal with.

However design is only part of the equation. Being green has nothing to do with whether they will have manufacturing issues. Porsche has had great designs for years but had lots of manufacturing issues. They finally had Japanese consultants come over to to show them how to build cars. The fact is that manufacturers are consolidating to reduce platforms and amortize the money required for things like crash testing and certifications in multiple countries.

Morgan and Panoz are not standards to judge by. Lotus does a lot of engineering work for other car manufacturers. The Lamborgini was a money loser for many years and changed hands many times until it was owned by larger car companies like Chrysler and currently Audi. Ferrari is one of the only ones with staying power and profitability and they are making a very big deal about the potential Ferrari for under $160K in 2008.

Most people on these forums are waiting for the whitestar or a less expensive car after that and they want something reliable that they can depend on. How many of these manufacturers you use at an example have built anything at a reasonable cost in mass production nevermind something reliable.

That doesn’t make things impossible, just very very challenging. I love a challenge

An idea I’ve had about “fast” charging. Since residential power lines can’t deliver the power fast enough, even with a 220V outlet, what about a charging station that stays “charged” by charging at night when rates are cheaper? This charging station would contain the cheapest form of energy storage possible (lead-acid).

This would allow the charging station to quickly dump charge the Tesla pack to a certain degree (not sure what it would be, maybe 90% full?).

Would something like this work? I think it will, just that it will take up space in someone’s garage. Maybe this would be how “charging stations” work. Instead of upgrading power delivery to charging stations, have charging stations store energy so that it can “dump” them to cars quickly.

Tony, There is no viable market for “Charging stations”. The gas station concept would be mostly dead.

With a 250-300 mile range, I would never need a charging station unless I was taking a road trip which is incredibly rare.

It would be more likely that I would rent a gasoline powered car for the rare trip that I didn’t take a plane to reach.

So how would a Charging station operator make money?

Unless the commerical 18 wheelers went electric, there is no viable way to make money with a Charging station.

Maybe a quick charge station every 100 miles on interstates could eek out an existance until the power density doubles or quadrouples and people would spend the night somewhere trickle charging before they would ever run out of juice.

I think their may be more profit in “JUMP” Starts for stranded electric car motorists. So maybe large disel generators on big trucks will run around charging stranded cars

Not sure why some folks seem to be upset that bloggers include suggestions with their discussion items. I certainly would like “free” suggestions pouring in for improving my company. I’m sure most would be impractically but some would surely be or use. Have you been able to make “use” of any blogger’s comments?

I missed that the battery cooling system attempted to keep the temperature between 25-35C at ALL times. Is this literal? TEG asked about the energy requored to keep it cool on a hot. You must have calculated this for certain conditions. Can you share this? Parking in the shade will save more than just protecting your halibut from frying.

You wouldn’t believe the number of ICE generator systems being installed in South Florida and the rest of the hurricane affected areas from the past couple of years. These run from $10-$30K for properly, permanently installed systems. I would sure love to be able to use my Tesla (or other) battery pack in conjunction with solar panels and perhaps a small portable generator for my emergency power needs. That would certainly the battery pack cost a lot easier to justify. This wouldn’t require much more than an inverter (could be internal to the car or external) and transfer switch. Do you have plans to include an inverter in the later models? 120V AC outlets can come in handy for other things too.

Hello!
I live in Stavropol Russia. I would like to know if this battery technology could be adapted to a wind power system for site energy requirements, with a centrifuge energy stabilizer (just an idea) to even out the charging process. I am dreaming of an energy self sufficient commercial freezer. I think the cycles of the compresssor needs would match well with your battery and motor technology. Have some thoughts as to who would be a good consultant to explore any synergies?
Sincerely
Jack Sapourn

—–QUOTE—–
Jack Gerdeman wrote on November 30th, 2006 at 2:42 pm
Is it similar to loss of gas mileage over time in a combustion automobile? So, after 5 years we give it a “tune-up” (new battery pack). How much do you anticipate a new battery pack would be (just a guesstimate would work)?
—–QUOTE—–

We can guess the cost of a new battery ourselves. Using the resources on this page, I would guess the cost of a new battery pack to no more than $33,608.52.

—–QUOTE—–
Mark wrote on December 10th, 2006 at 5:48 am
Making a ultra lightweight minimalist car isn’t what most people want.

Cars have doubled in HP over the last decade. Partly because of an increase in weight due to more rigid frames and safety features, but mostly because people want more power and are driving larger vehicles and trucks.

The Tesla Roadster is a very lightweight vehicle and I would be concerned about how I would fair in a collision with a typical vehicle which is 50%-150% heavier. I owned a Miata back in 1991, and at 2,100 lbs it always felt like a potential accordian when heavy traffic was around me. Now the Tesla’s structure may in fact be more rigid and it may have better safety features at a similar weight, but the average vehicle weight has risen noticable in the last decade.

While weight is the enemy for fuel economy and accelleration/decelleration, I’m hoping that the Whitestar has a stouter structure and a bit more mass bringing it closer to 2,800-3,000lbs just so that it can stand a chance out there in a wreck. With good aerodynamics, I’m assuming that enough batteries and a good regenerative braking system would still maintain reasonable range.

Statistically a LOT more people put a premium on safety than having ultra light weight go carts. There will also be more emphasis on range so that a person could drive as much as they wanted before spending the night somewhere. We are not a society of minimalists.

Tesla’s cars have to find a way to met peoples needs for them to be successful, rather than asking people to change their needs to fit the car.
—–QUOTE—–

I disagree. This is a trend that simply cannot sustain itself. If it continued unabatedly, then cars in 20yrs would weigh 10 tons!

have you looked at zinc-air batteries? i know they don’t have a high current capability but they have a high storage and light weight advantage. they may not be rechargeable yet, i heard they were working on it. there was an all electric car built a while ago that used Ni-Cad for starting and hills and acceleration, then switched over to Zinc-air for cruising speeds. it had very good range, i think a government agency in Arizona had it built or bought one from some company. this is not meant as a criticism of your design, in fact it seems almost too good to be true. i was just curious.

Hi,
I’ve recently read quite a pessimistic article, telling about the deplete of Lithium resources on Earth. According to the article, the problem arises with the violent growth of mobile devises market, and leads to considerable price growth on Li-ion mobile batteries.

Applying this information to the Electric Cars and, of course, the Tesla Motors Cars, some questions arise:
1. Is it possible to provide every car that drives our planet today, with a li-ion battery pack? Or we will meet a Lithium promlem instead of oil problem?

2. Do you have a plan on battery technologies, other from li-ion?

Why batteries? Didn’t Tesla build a wireless electricity receiver to power his friend’s dead electric car? Wasn’t Tesla’s grid wireless? Did he really burn a hole halfway around the Earth combining wireless communication with wireless power transmission?

A bit about battery technology, IT IS A HOAX… Trollies have been running around for a hundred years without batteries,recently technology has given us wireless charging capablities . Batteries may be needed for the mean time, until we get underground electromagnetic emitters that run up to our front doors, The technology of today will be blown away by what is to come. Electromags placed through all roadways to and from everywhere (a single form of motorization is archaic, comparing a single mode to a dual mode, the triple mode of power will be the standard). Mag-lev trains, Mag-lev big rigs, electricity being transmitted along with magnetic fields pushing and pulling, and oh yes, A SMALL BATTERY to get you up to the drive thru window and then back on the road again. Individually, what do these three things have in common: Corvettes, DVD’s & Electric motors? Historically speaking, The Stanley Steamer, Beta VCR’s & Batteries!

When doing initial reaserch on battery technology, what did you conclude about electromechanical batteries? Though EMB’s may not be practicle now, do you think they have a purpose in the future of EV’s?

Well Guys - I can see one reason to go with the current Li-Ion Batteries, not just the cost - but the maximum range in the current vehicle. now if they could do a test vehicle with a smaller battery pack of - say 100 mile range - with a choice of either NiMH, or Li-Ion, with two different prices according to cost and research requirements, they could determine - which of those two technolgies - potential clients would pony up for, and maybe even both would be desired, popular, and clients would pay for, not just an overwhelming single type, but a ballance of both types! For example - If you could buy a Tesla Roadster for 1/2 the current price at - let’s say $50,000.00 - are you ready to lay down your money today - and wait for your delivery in say - 6 - 12 months?

Would it matter to you that the car only got 100 miles instead of 250 miles to a charge. It would still be a ZEV, go 0 - 6 in 4 seconds (maybe less with a smaller and lighter battery pack!), have the same style, pizzaz; even head twisting capability! Would you buy it if it only went 50 - 60 miles on a charge, but cost $25,000 to $30, 000 Dollars? Would you write a check and certify it - mail it off to Tesla - for a 60 mile range Tesla Roadster, right now?

If so - would they be ready to have a production line with a variety of ESS installations streamined for easy installation and incorporation? Remember Switching from Li-Ion to NiMH requires a different Controller Logic in the Power Management System, and as you say - no heating, so - you might even need a completely different Environmental managment system for the battery pack, car, and cabin! Could Tesla do it? Would they do it? Maybe after they delivered - say - 200 units to clients - they would be able to begin more flexible choices, and so - keep a return on investment in their base prduct - the Roadster - continuing to deliver returns.

I - for one - think - If I could get a Tesla roadster that would give me a 70 mile range between charges, and would give me sufficient charge from a 110/120 volt home power source with a 15 amp breaker limit, to give me 10 15 miles charge in 60 - 90 minutes time - with a 70 mile base range - that such a car would cover 99.5% of all my current needs, and still be worth it for me to write out a check for $25 - $30,000 today!

Will they make one for me like this - I don’t know - but - it’s worth offering my readyness for such a parameter for when the time comes. Anyone else on the same page, needs, interests, and willingness for such a set of parameters as me?
I will continue working on electricfly in the meantime (www.myelectricfly.com)

Doug, I am not exactly sure where you got your information regarding NiHM vs. Li-Ion. The life cycle of a NiMH battery is about the same as a Li-Ion (400~500 cycles under real world discharge rates), they only have charge cycles of 1000 cycles if they are discharged at a rate of .1C. Plus NiHMs lose 1-5% of their charge per day. As far as energy density by weight Li-Ion beats NiHM hands down. Lets take two batteries of similar form factors and use the highest capacity ratings currently available. In one corner we have the contender for NiHM, the Panasonic 1.2V 4500 mAh (size 4/3AF), in the other corner we have Li-Ion contender, the AA Portable Power 3.6V 2600 mAh (size 18650). Both are approximately 18mm in diameter and 65mm in Length. The NiHM battery is 57g and the Li-Ion is 46.5g in weight. So for the NiHM battery we take 1.2V *4.5Ah to get 5.4Wh divide that by .057Kg to get a energy density of 94.736Wh/Kg. Now for the Li-Ion 3.6V*2.6Ah gets us 9.36Wh, divide that by .046Kg results in an energy density of 201.29Wh/Kg, twice the density of the NiHM. So if I guestimate, to get a battery pack with comparible stats to the one the Tesla has now, you would need 37% more batteries (over 9000 batteries). and you would be adding at least 50% more weight to the battery pack. So I really can’t see how NiHMs are better. Plus if nano technologies deliver on their promises, using shelf life, temperature, thermal run away as arguments against Lithium type batteries will be rendered moot, and energy densities of 1000Wh/Kg or more would be possible. Lastly, the cost of Li-Ion continue to decrease while the density keep improving. Only thing that made them really expensive in years of yore was the more complex construction process and lower volume demand. Now in the days of laptops, Ipods, and cellphones has changed that.

my two cents,

Greg

A soon to be available Aluminium battery technology developed by Partanen Europositron can make electric autos such as the Tesla and EV1 much lighter in weight while also dramatically increasing driving range.

Some specs on the Partenen Aluminium battery technology:

Energy Density/Volume: 2100 Wh/litre

Energy Density/Weight: 1330 Wh/kg

Cycle Life: 3000+ cycles

Minimum Working Temperature: - 40C

Maximum Working Temperature: +70C

Life: 10-30 years

Discharge Rate: Adjustable

A good example of the difference the Partanen Technology would have is in the EV1 by General Motors.

The total weight of the EV1 car without batteries is 816 kg. With the supplied EV1 batteries installed the weight goes to 1550 kg. The EV1 power supply consists of 26 Lead-Acid batteries of 53 Ah each, which weigh 736 kg i.e. almost half of the total weight of the car. Without recharge the EV 1 runs 145 km on highway and in city traffic about 115 km.

With a Partanen Aluminium technology battery weighing 60 kg, and with a volume of 40 liters it would have a capacity of 80 kWh. Installed in a 816 kg EV1 it could run 870 km on highway and 690 km in city traffic.

When Partenen Aluminium batteries are available for purchase I’m sure many Tesla owners will be taking a serious look at using them.

Full details are at: www.europositron.com/en/index.html

Noticed that Tesla is making a presentation at the Advanced Automotive Battery Conference, 2007

www.advancedautobat.com/LLIBTA/index.html

Session 4, Wed May 16th

Development of Advanced Li-Ion Battery Pack for EV and PHEV Applications
JB Straubel, Chief Technical Officer, Tesla Motors

Any chance of a write up in the blogs ? Sounds like lots of interesting stuff under discussion.

–
Roj

I would scrutinize the claims of AltairNano very carefully. It looks like this company was an oil & gas company (many name changes - raises red flags), then made a miraculous transformation to nano-tech only. These batteries will never show up in Tesla since they have an exclusivity agreement for EV use with Phoenix Motorcars. I don’t see the purpose of having this arrangement since it will limit their market, Phoenix Motor is not a huge GM type company that can demand these concessions. Additionally, being a former oil & gas company, you wonder if this is a ploy to patent up this tech and keep it out of the hands of the Big 3 for an EV application. It reminds of the Exxon/Ovionics deal which has been alleged to prevent Toyota from creating a plug-in.

AltairNano has a 16% equity stake in Phoenix Motorcars which is a private company and their only EV customer for these batteries. Therefore, there is no independent customer (like a Tesla) that is utilizing their technology in an EV application to substantiate their claims. This company could be a classic pump and dump, where the insiders cash in on all the hype. There is limited visibility since their only EV customer is a private company that Altair has a substantial stake. Phoenix Motorcars financials are not publicly disclosed and poor based on all the technology claims & big name customer AltairNano is alleging to be using their technology.

I could be wrong with my assessment, however, there are many questionable details about the company. I would like to see the bloggers and website question the fleet customers on the truthfulness of their claims.

AltairNano has issued a press release that had their batteries verified by an unrelated company, Aerovironment. They have also obtained another customer for their batteries.

What about Electrovaya’s SuperPolymer-Batteries and their EV Maya-100, they’re talking about over 200-300 kWh/kg and higher! PR-Gag? Or is this an alternative to standard LiIon? ( www.electrovaya.com/innovation/zev_tech.html )

Thoughts….
1/ People are kind of missing the point on the idea of building some kind of super-fast charger to use at home… that’s really not what you’re supposed to be doing with it (though I can see how it would be useful)… at this point in the tech development, and also distribution grid development, the idea is more towards overnight trickling where possible. Better for the batteries, better for your electical bill - better for your house circuits. You could probably come up with a DIY or third party small-capacity storage and surge-charge system if you needed a quick top-up on a regular basis, but it’s not what Tesla are aiming at right now For the record, having become familiar with my circuit breaker recently thanks to some shower trouble, my own house circuit has an absolute max of about 23kW (100A main fuse on a ~230V supply), minus whatever’s being used for lights, appliances, power shower, oven, etc… say 16-20kW as a practical charger max. Unless I was doing some serious amount of high speed, long distance driving (coming from somewhere distant and stopping off for less than an hour at home before urgently striking out for somewhere else similarly distant), this would represent an easily sufficient charge rate, and one significantly in excess of energy use rate on the road, which beats out most even low-powered EVs I’ve seen so far (which charge more at wall socket rates, which in my case would be 13A x 230 = ~3kW, or camp-site power hookups around 5kW). 20kW constant gets you about 60mph in a normal ICE car… probably a little more in the Tesla.

2/ Having read all that battery stuff, once I’m done being lazy here in the kitchen I think I’m going to check my laptop’s remaining capacity, top it up to about 30-40% if necessary, then remove it and and put it in the fridge (with the laptop plugged in), though this will require finding something else to counterweight the rest of the ultralight machine given that the screen will then be the heaviest component! But it has lost a significant amount of capacity since buying it last year (under 40Wh now, compared to 48Wh at purchase - still usable though, and “worth it” as it’s done a bit of road warrioring), which is concerning for car battery life…

3/ Sidetracking - does anyone know if similar battery-charge control software is available for laptops as for the Roadster? I’d love some thing which would not only forcibly shut the machine down at a certain battery percentage (which Windows itself can do), but would also shut off the charger at 90-95% to prolong the usable battery life… I’ve only found monitoring software so far, which has allowed me to track the charge patterns, which is useful in it’s way. To be fair to the built-in routines, they only charge at maximum, what I suspect as being about C/1.5 or so (~36W), for about 45 minutes / 55-60%, then rapidly slow the rate until it’s less than 10% of original - but it still finishes in just over 2 hours, quite interesting that, preserving the battery, reducing heat without vastly increasing charge duration; the pattern i’ve graphed also suggests it could potentially charge much faster, up to 1C at low % SOC, but is limited by AC adaptor capacity… might get a bit hot though!)

This is an excellent approach, partcularly for INDIA. My detailed comments would follow after I think over the various Blogs

I will be moving to the Bay area soon and the idea of an zippy electric roadster is quite appealing. My guess is the mild climate will allow the battery life to perform at its best and it would probably the best political environment where charging-friendly-areas may pop up. My company makes parts for the industry and many are designed to last considerably longer than the 5 years of the battery. Assuming similar quality parts are used in the construction of the vehicle, what would a replacement battery cost for year 6? Also assuming battery technology continues to improve/get cheaper, is there a plan to carry the model line long enough that an early purchaser will be able to upgrade their power supply as time passes?

How much is the replacement battery? I’m having a hard time finding this information on the website. It should be easier to find. Thank you.

Tesla… Thank you so much for your commitment to build a car that is going to pave the way for future companies to look up to. I am honored to live in this time when a company like Tesla will step out into an arena with the BIG DOGS and will soon be running the car industry. Pray to The Father for wisdom and knowledge and all will be given to you. I would love to walk into a show room with Telsa cars shining and glossy. And more, driving down the highway and seeing your product on the freeway. Thank you.

I agree with most on this thread (replacement battery cost and upgrading issues). The car sounds like an amazing innovation but the lack of information on this most important issue instills concern.

Please provide a reasonable estimate including installation and delivery costs to CA.

Thanks in advance.

How much do replacement batteries cost?

Boy are you guys something! Extend the wheel base of the car, reduce the battery pack by 75%, and put another one in the front. Use miniturized wave technology powered by wind in an under carriage under the car to recharge the battery not in use. Wrap the whole thing in one of those bladders that are used for Indy fuel cells, to keep the whole thing cooler using less energy. I expect a mock-up on my desk by next friday, 01/25/08, now get to it !!!!

“Corporation” is not a bad word. “Profit” is not a bad word. “Capitalism” is not a bad word. Many commenters seem to think that they are. I would like to remind all commenters, regardless of their politics, that corporations do not pay taxes. Rather, their taxes are all passed on to consumers of their products and services. When the tax burden becomes so high it can no longer be passed on, the corporation moves or goes out of business. I would suggest business friendly Texas would be a far better state to produce nearly anything - certainly autos - than say Michigan or Ohio. And California probably would require several years of negotiating environmental wickets with concommitant legal expenses prior to starting production. I firmly believe that the future, assuming we have one, is electric automobiles and nuclear power - which works whether the sun shines or not.

This looks promising

electronics.ihs.com/news/2008/japan-toda-kogyo-litium-ion-batteries.htm

Improved Lion cathode material licensed to volume manufacturer of LiOn battery precursor materials.

According to another article in “Technology Review” this increases energy density by ~30% , which is key for pure EVs, though it reduces power density. This formulation change is also supposed to improve reliability and safety as theres less chance of a thermal excursion and may even increase battery cycle life.

I can see how reduced power density may be bad for PHEV and EREVs where fewer/larger cells are used and you need to draw more power per cell during discharge/charge but for Tesla’s “many small cells in parallel” approach it may not be such a big deal.

Assuming that cells using this new formulation are drop in replacements for the current cells in the ESS this would potentially boost the current Roadsters range from ~220 miles to around 280. If the thermal characteristics are better too then maybe a lighter/less coddling ESS could be developed and if the reduced weight leads to increased range then maybe a full charge might get close 300 miles. Several “ifs” there

As this improves the cathode material there may even be future cells that combine this cathode with the silicon nanowire anode thats been described by the Stanford group which could potentially add another double digit increase to energy density. Assuming another 30% improvement then we’d have a Roadster with a range close to 350 miles, however, silicon nanowire batteries are currently laboratory prototypes only (to the best of my Googling knowledge) so this is pure unadulterated speculation.

–
Roj

Of course it’s a vanity/toy car at this point. But darrin’s cost comparison is apples to oranges. A 30 MPG gas car won’t give you the performance or style of this car, plus there’s the pollution aspect that is difficult to quantify in dollars. And Li-Ion batteries don’t just die after 5 years; they can last much longer. A more realistic comparison shows that the cost break-even of gas vs. battery will upon us shortly, at least for short-range trips. The real problem with battery is using it for long distances; think about how you would plan for a cross-country road trip in this car (it would be quite difficult). I really don’t want to run out of battery while on the road, since there’s no way to refuel it on the roadside like you can with a gas car.

A replacement battery pack will be quite expensive and depends on the battery capacity desired. A 50KW pack (using 2000mAh cells) currently would cost about $25K for the batteries alone, and then you have to add the cost of assembling them into the pack. The batteries for a 55KW pack (using 2200mAh cells) is about $35K. A 65KW pack (using 2600mAh cells if you can get them) would cost about $76K. The 2600mAh cells were available earlier this year (2008), but now appear to be in short supply. The higher capacity cells might actually be more economical in the long run because they have a higher discharge rating that ends up extending the life expectancy of the battery pack. Plus of course they give you more travel range between charges, and how much is not running out of battery worth? Priceless.

I live in a progressive small town on the northside of chicago called Glenview. We call it the northshore where mostly professionals live. Did you ever think of partnering with a village as ours and offer this car, put in a charging station and model it a an elecftic car community? This car strikes me. I am a pharmacist and I go mostly 20 miles sometimes 35 if necessary. I want a small car for my work. Here’s the problem with a 6 ft man. It’s tough on the back so we need visibility and comfort for sitting. I look for how I can sit up.. not get up and be in pain…..not worry about chicago cold weather and charge fails because of cold…….I do not need speed butr comfort for my wife and me….we’re baby boomers. Insurance costs state farm……and sevice if it fails and do I have to be towed all the time. Legitimate concerns. I will have grandchildren in 2 months…twins and I would like to take them in the car also. So what do you think fo my questions?
Jerome Kostecki

Hello,

I am very impressed by your development of an electric car. I live in Germany and just read about your car “accidentaly” in a report about the “IAA” (International Car Exhebition). The press and the car dealers in Germany do not really give Information in generally about electric cars…. which is quiet … . So, I have a financial question. how much does it cost to have an old Batterypac replaced… as you say that someone drives to the mechanic and its a one day procedure…. The price of 99.000 Euros is a price not everyone can afford… but how much will it cost to mantain the car (except charging costs). I believe that an electric engined car can change a lot of things…. do you think that you will produce a various type of ellectric cars, affordable for a wider range of people ( like Audi), or will you continue manufacturing roadster’s (like Porsche did) and perhaps a limousine?

I notice the tesela uses braking charging tech. why not put solar roof and trunk pannels in it . also my mechanic teacher from priverate school has been making wind generators from before I was born in the 50s and he told me in the 70s about his e3lectric car ideas and one iin particular no one Ive ever heard of has used its a constant when driving and doesnt creat drag. un fortunatly I cant give up his ideas his son is an areo space engeneer in ohio and ill contact him to see if he wants to give it away. you could attempt to reach the old man and ask him about his ideas on electric car generation . His name is ray woodruff and has moved to long view wa. I would like tro see this advanced but have several inventions of my own and have lost several and dont want to do that to anyone else.

How about offering the option of selling the chassis for a fraction of the cost and leasing the battery pack over a few years, insuring replacement of said battery pack when it needs to be changed (and then shipping the pack to proper recycling) ?

With regard to the “memory” issues stated on your website, I was with General Electric’s Battery Business Dept. for over 10 years where we produced sevearl types of NiCd, NiMh, SLB, LiMnO2, and other batteries. The NiCd “memory” phrase was coined by a government contractor that purchased GE military sattelite batteries where the specific regime of charge and discharge was regulated by the orbit of the sattelite around the earth using solar charging. When the sattelite was asked to perform a task outside it’s very regimented regime it did not comply. Repeated laboratory testing indicated that due to the regimented charging scheme , the battery voltage was lower when called on to perform past it’s original design due to a crystallization buildup on one of the battery plates. We always cautioned clients that a “voltage depression” could occur if they had sensitive low voltage thresholds or a cyclic charge/discharge scheme. The capacity was always there but at a lower voltage. A complete discharge and charge cycle eliminated the formation of crystals on the electrodes which raised the potential back to 1.2 volts per cell. I’ve often said that when battery operated automobiles can start to get 300-400 mile range with a 1-2 hour charge cycle we can say good-bye to internal combusition engines, looks like your rapidly approaching that milestone, best of luck. Pat Harvey

I am just curious why the battery must be so large and heavy? Apple recently released a new battery with a shape that is flat, light, and takes less space. Also, will that be a possibility for the future Tesla?

How the batteries react during a extreme weather in New York during the winter or in death Valley in Nevada?

In case you didn’t understand Lebierre’s comment here is a translation:

Sirs,
Do you think that you will open a dealership in France in the near future?
Thank you in advance for future responses gentlemen, best wishes to you.
Pierre Lebierre.

I thought you would like to know that there is interest in Europe which is growing very rapidly in it’s green concerns.

What is the cost of a new battery pack when it comes time to replace it?

I wonder the same as many of these other posters: The cost of a new battery pack and service availability outside CA. I see you offer ‘roadside assistance’ and what not - but does that cover the cost of transporting the vehicle from it’s location to a service center (which may be hundreds of miles away)

The cost of the battery and life-span is also very important to me. I can easily put 50K miles a year on my car being in rural America. The battery might have to be replaced every 2 years. But money, to me, is not as important as making the move away from a combustion engine. When GM sold its E-95 battery technology to Chevron/Texaco, it was clear that the other car companies have no intention to move into a green technology of electrical vehicles. Even their feigned attempt to produce a hybrid car is window dressing.

I can see where Tesla (which is now my favorite car company) can easily move into fuel cell as well as battery along with integrated solar to make the best green car on the market.

The price has to come down. I am encouraged by the Sedan S at a price of 50K. It would be a stretch to pay for that, but I think it would be worth it.

I am doing a research study of battery life in hybrid and EV and their impact under special situations.

Hypothesis:
Lets say a Tesla Roadster car is just driven for a week every 6 months for a period of 5 years (warranty time)

What will be the expected battery life of such battery under that situation?

Is there any special care that the battery will need to have if the car is used under this situation?

Is there any way to improve the battery life under that situation?

I drive about 20K miles/year, currently in Prius, 53 mpg average. 400 gallons petrol/year. 2000 gal per 5 years.
I’m strongly tempted by The S model. I wish Tesla DNA had been transferred to ailing infrastructure of Detroit (ala GM) to go into mass production, make this even more an everyman car.
I have concerns about being an early adopter though : battery life and cost, and true ecological cost of production (ie battery production). Of course the ecological cost of making Prius batteries and the car aren’t that much different.
Electricity to run Tesla S at 0.3 kw/mile per year would be 30K kwh for 5 years, at 10 cents kwh is $3000 (or $600 per year)
Battery will be no less than $15K at 5 years (could be $20-30K, if you figure there are 6128 cells at $5 per cell, even with economies of scale), so figure no less than $3K/year for battery cost.
Electricity (currently, no pun intended = $3600 per year in Tesla, Gas = $1,200 per year in Prius. Who knows, in 5 years batteries go down to $10K and best case kwh stay low, and gas goes up.
Electric =$2600/year, Gas (@ $8/gal) =$3200/year. So at some point there is a crossing of fuel costs.
What is the footprint for battery production (millions of cells just for 1000 cars in 2011)? Hard to measure. Lots of lithium, mining, transport of materials (petrol based cost). Is there enough lithium on the planet to have everyone drive something based on this (in China and India also etc)?
Tesla $50K upfront, Prius $25K upfront. So to run the Tesla currently costs, for me, roughly $5-10K more in fuel over 5 years, and $25K more upfront (say about half that for resale of the vehicle, or $12K), equals roughly $10-20K more over 5 years. Rough minimum of $2K more per year than Prius, which may be catching up with PHEV (plug in models by then?)
But then there’s the cool factor. Not to be underestimated. I’m not immune to vanity. Some people pay $1K per year for their iPhone service and $1K per year for their Starbucks service. I love the idea of chucking Big Petrol. With enough photovoltaic production, I’d get a bumper sticker that says “This car is Nuclear Powered” and another that said “The only safe Nuclear Power is 93 million miles away”. However, nukes are back big time.
I like the post about cheap care, lease the battery. This would be a great model. Much like Agassi in Denmark and Israel. Check out article
www.wired.com/cars/futuretransport/magazine/16-09/ff_agassi

What is the exact battery capacity in kWh. I have seen number ranging from 50 to 55 kWh, but would like to know the exact value.