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Tesla Battery idea for faster charging and safer and longer drive

For 18650 battery, when the voltage cannot produce acceptable amount of output necessary for powering up the load, the charger's built-in threshold mechanism will tell the charger to display RED led until such time that the voltage output is sufficient, that it would display a GREEN led and stop charging.

All chargers have a built-in threshold for when to accept a battery for charging and when to stop.

As far as we all know, Tesla Model S uses the Panasonic NCR18650A 18650 battery which has the capacity of 3070mAh and output of 3.6v.

What if Tesla would change the threshold of necessary voltage for battery charging?

Normally a full charge 18650 volts would produce 3.6v and if the voltage drops to 3.0v you can put it in the charger.

So if Tesla has a threshold of 3.0v for each battery, the mileage would be empty.

What if Tesla would increase the threshold to 3.4v, so that the batteries will not be drained and charge at full-cycle that is faster to charge, because we just need to fill up 2 volts for each battery. And what if they double the number of the battery installed so that it would match the fully drained profile of a single stack battery, that would result to a really fool-proof reliable car.

A 2 battery indicator in the HUD, the first one is the threshold of 3.4v that when it reaches this voltage it is recommended to charge the car, and the actual full capacity of the battery is in the 2nd indicator showing the full draining capacity.

``` +--------------------------------------------+ |+--------------------+ | ||battery is @ 3.4v | | |+--------------------+ | +--------------------------------------------+ || | | ||threshold at 3.4v | | ||recommending drivers| | ||to charge at this | | ||point. | | | | | | | | | | | actual full draining capacity of battery | ```

@joelbryan | MARCH 22, 2013: What if Tesla would increase the threshold to 3.4v, so that the batteries will not be drained and charge at full-cycle that is faster to charge, because we just need to fill up 2 volts for each battery. And what if they double the number of the battery installed so that it would match the fully drained profile of a single stack battery, that would result to a really fool-proof reliable car.

You mean 0.2V? This can be achieved by the driver of the car not running down the singe stack battery fully. Also, if you double the number of batteries, you would increase the weight of the vehicle to a point where range would suffer vs. a fully depleted single battery car. Cost would also increase and the car would not not be attractive to buyers.

ecigarettes uses 18650 batteries, I'm using a Provari mod which blinks when the 18650 battery is at 3.1 volts, though it's not fully drained but it is the recommended threshold voltage to charge the battery.

Imagine the possibilities, I think it would be really interesting to have a tesla with this configurations.

1. increase the threshold of tesla car to 3.4v, so that is only 0.2 volts depleted, resulting to fast charging and huge amount of emergency reserve.
2. dual-stack batteries, with each battery only depletes 0.2 volts, and if all those batteries depletes 0.2 volts, it would match the profile of a fully depleted single battery car, again the car is faster to charge, and having a huge amount of emergency reserve.

How does repeating what you originally said help clarify things any? You're completely ignoring the parasitic drag caused by the increased battery weight. Besides, I don't know that it's a fair assumption that what's good for an electric cigarette work for electric cars. Why would you even mention such a thing? :puzzled:

I don't own a Tesla but I've seen a couple and I think they're fantastic. No idea when I'll be able to afford one, but electric cars are definitely the way to go, and kudos to Tesla for making it happen.

One thing strikes me about the "problem" with charging the batteries: I might seem a bit naive, but has Tesla considered batteries that can be easily removed, as you would remove batteries in any other electric device?

I would think that if batteries could be slid out from under the doors, they could be replaced in minutes. Batteries could then be "rented" as you rent, say, a gas cylinder. Just as you take back an empty gas cylinder and buy a full one, you only pay for the gas, and exchange the cylinder. You pay for the first battery, then it's just a matter of changing it out when and if you need to, or are in a particular hurry. Charging stations could have a stock of ready charged batteries for people who need to get back on the road ASAP.

Then you'd have the option of having your car charged at a recharge station (and wait for it to charge) or for a little more, just have a ready charged battery changed out for the "empty".

I'm sure the folks at Tesla would have thought of this one, and I would imagine there are huge impracticalities in designing an easily changeable battery.

But...just a thought...

@jack7223, yes the idea of renting batteries, swapping batteries, etc, etc has been discussed a lot. The batteries in the Model S are designed to be replaceable without tearing the car apart, but so far as we know, not necessarily designed for swapping constantly.

There are a lot of logistical and business/economical issues when it comes to the idea of battery swapping. I'm not saying it's impossible, but I think it's more practical to try to build bigger and better batteries and faster charging systems, so that there is less desire to swap batteries.

Also, consider that swapping batteries is really only to satisfy the desires of people switching from ICE to BEV. We are used to being able to fuel up easily and go 300 miles with ICE, so we think we need that, but the truth is, the vast majority of people hardly use that "feature" of an ICE on a regular basis.

In my opinion, it's a much better tradeoff for a majority of people to simply handle the lower convenience of the extra planning necessary to take an EV on a long trip once in a while in order to take advantage of all of the day-to-day advantages of owning an EV. Sure there are some people who this won't work for. There are people who have 100 mile commutes or who drive around all day for work or haul lots of cargo, etc, etc. These folks are in the minority. We don't have to solve the problem everyone at once.

In my opinion, battery swapping would only really be convenient if we had batteries with extremely high energy density (like the same energy as the Model S battery, but the same size and weight as an automotive 12-volt battery), such that the user could drive to some "gas" station and easily swap the battery herself. Then it would make more sense to me.

I really don't think taking your car into some kind of shop, where trained technicians would be needed to swap the battery, would be practical, even if it could be done in ten minutes.

@jack7223

Renault has (is?) attempting to create such a battery-swapping system using its Fluence Z.E. car, but as this has been announced some years back, there has been Z.I (Zero Interest) it seems.

@olan;
+1

The logistic and financial requirements of maintaining a circulating stock of batteries and the robotics to swap them are formidable. Elon summarizes it as "can't make a business case" for doing it. Indeed; Better Place is spinning its wheels and making little progress, e.g. Billions have been sunk into it, more than has been invested in TM, I think. As with Fisker, the founder is gone, replaced by bean counters and hoarders. Always a bad sign and prognostication. Elon, meanwhile, continues to fly high.