I have read a few different articles now that talk about all the harm that is done from producing the batteries for electric vehicles. John Peterson on seekingalpha.com has had a few articles, and now today there's another article in the Wall Street Journal about the "Dirty Secret".
I have been digging through a lot of the source documents for these articles and it's fascinating how little the people who are making this research "understandable" for the public understand.
For example, one of John Peterson's articles he was talking endlessly about the impacts of a battery electric vehicle (BEV) and then linked all these studies to prove his point. When I went digging through all his sources I found that the estimates for the BEV were all coming from an initially small pack that was then "scaled up". So for example, maybe the original research was based on a 4 kWh battery pack. Then Peterson and the others multiplied the figures by 15 or 20+ to get to a Tesla 60 or 85 kWh battery pack. They simply fail to mention that all the errors of measurement then have to be multiplied by 15 or 20+. When you take into account the large error introduced by scaling, all of the results are meaningless. A small error in the initial model translates into a huge error at the final analysis and renders meaningful statistical comparison impossible.
Today's WSJ article there's a similar problem. This article and Peterson cite this article from the Journal of Industrial Ecology: "Comparative Environmental Life Cycle Assessment of Conventional and Electric Vehicles"
Dig into the source article, and you find this statement about how they estimated the size of the battery for their electric car:
"Battery masses of 214 and 273 kilograms (kg) were selected for LiNCM and LiFePO4, respectively, so as to have equal charge capacities of 24 kilowatt-hours (kWh)."
Well here's the problem... the Panasonic cells used by a Tesla are about 46 grams each. There's 7000 of them, meaning the weight of the cells in the Model S 85kWh is around 322kg. Maybe you could use the total weight of the pack, which I think Tesla has said is closer to 450kg.
But if you scale up the 24 kWh pack used in the study by a factor of 3.5x, you would find the study implies an 85kWh pack should weigh 758 kg. That's double or more the true weight of the batteries used in a Model S.
The Journal of Industrial Ecology article also seems to use a scaling methodology for results based on another study. While I couldn't find the other study online, it looks like the author is going to have the same problem where scaling a small battery pack up is going to magnify all of the errors.
I don't know how long Tesla is going to stand by while all these "researchers" spew out B.S. I for one would like Tesla to have a serious study undertaken about the environmental impacts of a Model S.
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