Type in the words Li-ion batteries and you will find a series of articles all leading to this one written by John Petersen and published in Seeking Alpha on March 23. And the subject of the article is fascinating: How Cheap Beat Cool in the Chevy Volt. By cheap, the author refers to the fact that GM has selected, Li-ion batteries with prices in the $600 to $700 per kWh range as opposed to the $1,300 to $2,000 per kWh range. The article goes on to say that the battery will come from a Li-polymer chemistry instead of the more expensive Li-phosphate or Li-titonate.
But Li-polymer, has its share of challenges. The first problem relates to its safety record (it does not do so well in cell phones and lap tops) Li-polymers also appear to have a shorter product life cycle than their higher cost alternatives. So GM looked at the various alternatives and came up with a workaround, a T-shaped battery pack that sits in front of the rear axle and runs forward through the space that used to be taken up by the driveshaft. That 400-pound battery pack is made of armor plate!
Take a look at Lithium ion batteries or Li-polymers and armor plate and little public information exists on the subject. If someone were to ask us to guess what type of armor plate covers these new batteries on the Volt, we’d guess aluminum due to its significant weight advantage over steel. Unfortunately, we can’t seem to find much data. It’s time to start talking to our friends in the automotive industry!