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Imagine yourself strapped into a Tesla Roadster speeding down a rough cobblestone path intended to cause so much agitation that the ride stops being fun and starts becoming more like work. It's just a typical day at the Motor Industry Research Association (MIRA), an engineering and testing facility where we are punishing two of our Tesla Roadster Engineering Prototypes (and several of our engineers as well!).

By now most people know that the Tesla Roadster is powered by Lithium ion (Li-ion) batteries. But here are a few things about our batteries you might not have heard. Our battery system – or Energy Storage System, as we like to call it – is comprised of 6,831 individual Li-ion cells. It's roughly the size of a storage trunk and weighs about 900 pounds. Nestled securely in the back of the Tesla Roadster, the battery system is the secret behind our four second 0-60 mph acceleration and phenomenal driving range. To achieve this kind of performance, we were meticulous about our battery technology selection. Batteries are not perfect – no doubt about it. Though market forces continue to drive improvements in batteries, the Li-ion battery system in the Tesla Roadster represents the very best of today's commercially available battery technology. These Li-ion batteries are a whole lot better than Nickel-Metal Hydride (NiMH) cells and lead acid cells found in EVs of yore, but they too have their limitations. One of the most difficult challenges in battery design is increasing energy density while also maximizing battery life span. Li-ion chemistries have achieved better combinations of these parameters than anything that has come before. Yet there is still a tradeoff between energy and life, even within the family of Li-ion.

Don Cox is a Professor of Electrical Engineering and the Harald Trap Friis distinguished chair at Stanford University. He spent 25 years at Bell Laboratories and Bellcore developing revolutionary technology for what is now referred to as "cellular phones." He has served on the board or as an officer of several Silicon Valley public companies and sits on technical advisory boards of many others. In this week’s blog entry, Don explains why he wanted to be among the first customers to receive a Tesla Roadster. (Don, pictured above with his wife, Mary, checks out the Tesla Roadster.)

My wife, Mary, and I were invited to be a “guest blogger” on the Tesla Motors website. This is a big honor for us. It is an easy task because of our high regard for the Tesla Roadster and the people at Tesla Motors.

We have had a long-standing interest in electric cars because of their potential both to help reduce our country’s dependence on foreign oil and to save our environment from pollution emitted by cars that use internal combustion engines. We thought you might be interested in our experiences and investigations in becoming Signature One Hundred members, the group that has reserved the first Tesla Roadsters to come off the production line. Our story might be called, “How we fell in love with the Tesla Roadster and Tesla Motors.”

Bob Bressler is a customer of Tesla Motors and owner of Bressler Vineyards, a small producer of super-premium Napa Valley Cabernet Sauvignon. An expert in the Internet and networking technologies, Bob’s career prior to becoming a full-time vintner spanned executive positions at Sun Microsystems, 3Com and BBN. We asked Bob to share his perspective on electric cars and the Tesla Roadster.

Why did I order a Tesla Roadster? Believe me, my wife has asked me that question many times. I guess there is no single reason – but a long list of them.

A bit about motors, magnets, AC and DC, and weird little widgets called IGBTs, all the while trying to answer some more of your questions. (And yes, we are opening a Detroit office, but that’s another story.)

This blog continues to attract some fascinating questions and perceptions regarding the philosophies of energy consumption, alternative fuels, well-to-wheel efficiency and other significant issues that affect us all. Then there’s the technology of the car itself with its lithium ion battery pack, onboard charging system, power electronics to handle the immense energy available and that little motor that blasts you towards the horizon at warp speed……Linking all these systems and their safety monitors involves more computing power than the combined total on board all the cars I’ve ever owned. You could probably add your total in too!

So, apart from the new high tech stuff, what else do we do at Tesla Motors to ensure that our customers can enjoy this unique offering?

Many of you have asked me about several alternative technologies and why they are not used in the Tesla Roadster. These technologies range from other existing battery technologies (e.g. lithium iron phosphate) to technologies that are on the horizon (e.g. ultracapacitors) to impossible technologies that ultimately boil down to perpetual motion. I will try to address as many of these questions as I can this week.

I know, I know. There are at least a dozen good topics from all your responses for this week’s blog. But I can’t help it – we had such a great time at the Concours d’Elegance at Pebble Beach this weekend that I have to tell you about it.

I continue to be blown away by the number and breadth of responses to our blog. Thank you and keep them coming! Once again, I can’t possibly answer every question, but I will try to answer a few more today.

Holy smokes! There is no way I can respond to all your comments, but thank you everyone for writing. This time I will discuss one common thread that many of you raised: what exactly is Tesla’s relationship with Lotus? Along the way, I will address a few other threads from your feedback. Once again, I am writing without Marketing’s filters, so I apologize in advance for any “pc” slips.