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I am very confused at the moment about some details on the battery packs and the prices and all the blah blah. If tesla can produce a luxury sedan for 60,000 with an electric range of 200+ miles then why in the hell does the volt cost 40k and only capable of 40 miles electric?

The battery pack is suppose to be the expensive part and if the volts battery pack is 10,000 then the battery needed for the tesla sedan would cost 50,000 alone? Someone, smarter than me explain this to me? I am curious how the largest automotive company in the world is being trumped in price/performance by a startup electric car company?
 

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Tesla is using "commercial-off-the-shelf" Li Ion cells of a chemistry designed for laptops, which means slow power draw with maximum energy density. They had to use many cells in parallel to get the peak power output needed for performance, which had the benefit of also giving them a long range. Tesla spent a lot of time and money designing a battery pack to ensure those cells don't catch fire.

GM is using a proprietary Li Ion chemistry which will NEVER catch fire, while delivering high power from only a fraction of the number of cells. This allows them to provide good performance from fewer cells, at the expense of overall range. GM is able to extend the range with a gasoline / ethanol ICE, a diesel ICE or a fuel cell, at a much lower cost than simply adding many times more cells.

The smaller cost delta you decry is then a result of GM using a more expensive, proprietary Li Ion chemistry, while offering seating for 4, instead of 2.
 

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Jason... correct me if I'm wrong but there is also the life cycle of the battery to consider...

GM wants 10 to 15 years of life cycle as Tesla is less then that... I don't have the exact life cycle, I'm sure Jason does :)

So that's another aspect that explain the higher cost for batteries
 

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-GM is conservatively estimating 50% (30% to 80% SOC) usage of the battery and 10 years life. Tesla figures nearly 100% battery use in there mileage figure and expects 5 years of life.

-GM is having 2 teams vying for the Volt contract and developing batteries just for the Volt. Tesla's battery pack is comprised if 6000+ off the shelf laptop cells with Lithium Cobalt cells. These cells have lower power density but higher energy density and have significant thermal concerns to be engineered around. The LiCo cells are also significantly cheaper at this time because of production volume and numerous competing manufacturers.

-The Tesla BEV sedan will run its battery range and then need an outlet to be recharged. For standard 120V/15A outlets this will take a long time to go 0% to 100% SOC (like 40 hours or so). The Volt has an ICE genset with all of the accompanying accessorries (fuel pump, fuel tanks, fuel guage, fuel lines, gas filling port, exhaust system, etc. etc.) but you can refill the gas in 5 minutes at any of the thousands of gas stations around the country.

-The charge sustaining moded of operation does not come pre-programmed for free either. There is a lot of additional engineering needed so the car runs seemlessly in this mode.


These are the most obvious cost differentiators, but I'm sure there are a few others.
 

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The smaller cost delta you decry is then a result of GM using a more expensive, proprietary Li Ion chemistry, while offering seating for 4, instead of 2.
Don't buy the press oversimplification that Tesla's battery is simply "laptop batteries" - the chemistries are similar but tesla's pack is purpose-built.

Meanwhile, GM's Volt team is testing batteries from suppliers, including Continental A.G. teamed with A123, and Compact Power, a subsidiary of LG. Which could get interesting, what with A123 successfully sued for stealing their chemistry from others. In any event, it's not "proprietary" vs. "off the shelf" - in both cases it's automotive parts supply as usual.

Further, the term "Li Ion" isn't all that accurate when used to discuss a specific type of battery. Lithium Ion applies to a group of batteries, ranging from cobalt oxide (the type previously used in laptop computers, with flame potential as they produced oxygen while charging) to iron phosphate (the sort now favoured for electric cars, though being larger and heavier). Cobalt Oxide batteries weren't a "chemistry designed for laptops" but simply the chemistry thought to be the most compact and efficient at the time, used in many products including laptops, cellphones, etc.

Even then, there's lithium ion iron phosphate (LiFePo) prismatic and cylindrical, with identical chemistries but different internal properties due to their construction.
 

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Tesla is using "commercial-off-the-shelf" Li Ion cells of a chemistry designed for laptops, which means slow power draw with maximum energy density. They had to use many cells in parallel to get the peak power output needed for performance, which had the benefit of also giving them a long range. Tesla spent a lot of time and money designing a battery pack to ensure those cells don't catch fire.

GM is using a proprietary Li Ion chemistry which will NEVER catch fire, while delivering high power from only a fraction of the number of cells. This allows them to provide good performance from fewer cells, at the expense of overall range. GM is able to extend the range with a gasoline / ethanol ICE, a diesel ICE or a fuel cell, at a much lower cost than simply adding many times more cells.

The smaller cost delta you decry is then a result of GM using a more expensive, proprietary Li Ion chemistry, while offering seating for 4, instead of 2.
I popped off the same way over at another forum regarding Tesla's batteries and was very surprised at the response of Tesla's technology. If you're curious:

http://www.teslamotorsclub.com/technical/1070-compare-volt.html
 
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