主题：【整理】电动车对电池的要求 -- 橡树村

TESLA使用的是钴酸锂电池，并非A123的磷酸铁锂电池. 信息来源可见最近的季报CONFERENCE CALL, 内容见最后，里面也提到了使用松下电池的计划

不知道为什么回复了一篇就不能再回了，对系统不了解，是通宝不足吗（－2）。希望大家支持给宝什么的，能让我再回复就成。最近对电动车很感兴趣，主要是从股票角度研究，希望能和大家交流

TESLA的特别之处是在电池系统上。钴系电池也就是笔记本上的，应该是技术最成熟量产最高的，能量密度也高（同样的18650，比A123的磷酸铁锂高一倍）。但热稳定性差，安全性低，因此TESLA使用非常复杂的系统和普通现有电池，走了一条与众不同的道路。别的公司则在发展车用专用电池上下手，电池起点低，研究空间大。

从网上的信息来看，TESLA ROADSTER采用的钴酸锂电池是2.2Ah，按每节45克算，电池能量密度是170Wh/Kg, 整个电池系统则120Wh/Kg,容量53度.

与TESLA相比，即将上市的NISSAN LEAF，使用锰酸锂电池，电池能量密度～140Wh/Kg, 整个电池系统300kg, 容量24度，电池系统能量密度仅有80Wh/Kg，比TESLA落后不少。结果是里程仅100英里，还是EPA City Test, 对应TESLA是230英里，EPA city/highway combined cycle

松下18650钴酸锂电池主要是2.9Ah, 最近开始生产3.1Ah, 预计在2012年达到3.4Ah,这样能量密度还有50%的空间可以提升。另外TESLA说今后将使用松下的nickel-cobalt-aluminum电池，用钴量只有1/3，造价还有下降空间。

另外你说的火箭发射项目，应该是CEO ELON MUSK另外投资的SpaceX，不在Tesla业务内。ELON MUSK是Paypal创始人之一，商业头脑应是极好的

Conference Call of 2Q10 Earnings:

Elon Musk - Tesla Motors - Chairman, Product Architect & CEO

It sounds like you are probably referring to the factory cost reduction we are talking about in the IPO presentation where we show the Model S factory cost per kilowatt hour being about 44% of what Roadster version 1 was and Roadster 4 being 69% of what Roadster version 1 was. So essentially what we are saying is that we are able to drop the cost per kilowatt hour by roughly, to roughly half of what it was when we started with Roadster going into Model S.

So the improvements there come from both the battery pack level and at the cell level. So we have been able to increase the packing density of the cells considerably, so there is almost a 50% increase in energy density at the module level for the battery pack. So they are very densely packed and installed with enough room to fit the liquid cooling loop in there and maintain tack safety. So that even if one cells goes in thermal runaway it does not cause a cascading effect and cause other cells to go to the runaway.

This is actually a very hard call to make. But the more energy you pack into those -- the higher the energy into the pack the harder this problem gets. So if you want to do a lower energy density pack it's a much easier probably than a high energy density pack, which is (inaudible) reason and common sense.

We have also changed the cell chemistry to one which has a lower fundamental cost. In the Roadster the cathode was or is cobalt. In the Model S it's a nickel cobalt aluminum cathode, so we are using roughly a third as much cobalt as we do in the Roadster.

The cost isn't strictly speaking, I think, a rate earth element, but it is expensive. It's the most expensive ingredient in the battery pack so being able to reduce that to a third of its level in Roadster gives us a much lower material cost at the cell level than was previously the case.

And the energy density is actually higher so it's about a 15% increase in energy at the cell level going to the new chemistry. We have worked closely with Panasonic to develop a cell that, although it's in the 18-650 form factor, so it's 18 mm diameter by 65 mm in length, the internals of the cell are actually optimized for an automotive application rather than a laptop application.

So it's because the external form factor is still 18 650, we leverage the economies of scale that Panasonic has in the factories that are able to nonetheless have an automotive-optimized cell. The changes associated with that cell, that is intellectual property that Tesla owns and has a platform patent on. So that is something that in the future as we look to achieve attain a second source for our cell manufacturing we can transfer those changes to the second source as well.