Zoomit said:
Crap..cut-and-paste error to my old data. The previous post is corrected now. Also, here's the correct link:
https://teslamotorsclub.com/tmc/media/20161029-bev-comparison.116204/full
Excellent. I was guessing that might be the case.
Where did the speculation that the Bolt EV has a 70.2 kWh battery come from? That seems very unlikely.
GM had said in earlier interviews that the usable versus nominal battery capacity in the Bolt EV would be roughly similar to the Spark EV. You show the Spark EV as being 19.4 kWh nominal and 17.7 usable which is a 9.6% spread.
If applied to the Bolt EV with the assumption that the usable capacity is 60 kWh that would only result in a 65.75 kWh nominal estimate.
And actually, GM has published multiple documents stating that the Spark EV nominal battery is 18.4 kWh rather than 19.4. That would be a spread of 4% which if applied to 60 kWh usable would result in 62.4 kWh nominal, a much more believable number.
For example:
http://media.gm.com/media/us/en/chevrolet/vehicles/spark-ev/2015.tab1.html
The drag coefficient and thus the total drag area is also a bit speculative. I know that the Bolt EV's exterior vehicle designer was quoted in an interview as saying the Cd was .32 but I'm not aware that GM has ever published that number itself on any public specification sheet or online press release.
However, GM did apparently give out a specification sheet to a few journalists it briefed back in January and that is where Car & Driver got the 25.8 sq ft frontal area number that they published back then. They also published the Cd as .312, consistent with the specification sheet that GM gave them.
It's not at all clear that anything has caused that January .312 Cd value to have changed.