Understandable and thanks for posting. My comment was not on the value of fast charging, just that it will likely not matter to me one way or the other. Then again, I'd likely get the Bolt EV DC charging upgrade, just in case.It will probably be irrelevant for most, but I have been approached by a number of people who want to know about the long-range viability of a Bolt EV.
The problem is that it's not that simple. What you get in 15, 30, etc minutes depends greatly on the starting SoC. Here're some graphs from my slightly optimistic battery model. See the bottom one to see how much range you get in 30min. (The flat line from 92 to 100% is an error, it should be linear to zero at 100%.)I, too, am a much bigger fan of providing average charge rates. The peak numbers are good as a sales pitch, but people want to know about how much power (or range) they will get if they plug in for 15, 30, 60 minutes, etc.
While I'm pretty confident that we'll discover that the Bolt will charge faster when someone is able to hook it up to a charger with a higher power rating, we should keep our expectations realistic. The higher charge rate will only be realized at lower battery states of charge, and if it tops out at 60KW then it's only 20% more than what current chargers are capable of. You have to combine that with the fact that few people traveling long distances will arrive at a charger with 0% in the battery, because the charger may be out of service or in use - so you have to keep some "Plan B" charge in reserve.All information indicates that it will charge faster...
If the peak is 60 kW, that's actually 33% faster than the best we can currently achieve. Maybe I'm just a risk taker, but I've been more than comfortable with arriving at DCFC stations with 5-10% SOC. Even if you are super conservative, 20% SOC should give you more than enough buffer. And that would still result in a fairly impressive improvement over current charge rates (close to 25% faster).While I'm pretty confident that we'll discover that the Bolt will charge faster when someone is able to hook it up to a charger with a higher power rating, we should keep our expectations realistic. The higher charge rate will only be realized at lower battery states of charge, and if it tops out at 60KW then it's only 20% more than what current chargers are capable of. You have to combine that with the fact that few people traveling long distances will arrive at a charger with 0% in the battery, because the charger may be out of service or in use - so you have to keep some "Plan B" charge in reserve.
When you combine all these factors, you're probably looking at 10% or less improvement in charge times to the 80% state of charge level, which translates to about 6 minutes over an hour. Yeah, it's nice if it charges that little bit faster but it's not going to change anyone's opinion of whether or not it's fast enough for them.