The batteries are being replaced because of a manufacturing defect. From the public description I believe that upon swelling at full charge, an arc could occur internal to a battery cell and start a fire. The defect is apparently rare, but there is no way to determine if a cell has the defect without destroying it.
GM discovered the manufacturing process that caused the defect and made changes so newer cells do not contain the defect. However since there is no way to determine which cells made under the old process are bad, GM decided to replace all the battery packs made from cells using the old process. This includes your 2020 car. As for your range reduction, did you really used to drive 260 miles per charge and now can only drive 220 miles per charge? Driving the car from full charge until the charge is completely depleted is the only way to determine the range. If you are noticing that the range estimate displayed on the driver’s information screen previously presented 260 and now presents 220, this is probably more of indication of how you have been driving. Did you have to software update that limits the charge to 80% installed? This will also effect the range display. The estimates are calculated using a bunch of ad-hoc heuristics. The best thing you can say about them is that they are inaccurate (except if it displays 0). Having said that, the estimate combined with the trend bars is quite useful. The trend bars indicate how much better/worse you are driving compared to the estimate. If you always drive in a manner that keeps the trend bar above the range estimate, you will always beat the estimate. I find this combination to be a very intuitive and effective interface. Ed > On Dec 6, 2022, at 12:12 PM, Mark Hanson via EV <[email protected]> wrote: > > Hi folks > I bought a new Chevy Bolt August 2020 (now has about 40k miles) and a year > ago got a letter from Shelor Chevy saying they were going to replace the > battery, now just crickets (dealer doesn’t know anything) Does any Bolt folks > know if they just replaced the 2017s and not the newer cars? The range has > dropped from 260 to about 220 in warm weather. I noticed that Chevy is the > only one that doesn’t say to charge to 80% for local trips , probably why > they’ve had some 100% charging fires (clueless owners charging hot to 100% > daily). > Have a renewable energy Christmas > Mark > > Sent from my iPhone > _______________________________________________ > Address messages to [email protected] > No other addresses in TO and CC fields > HELP: http://www.evdl.org/help/ > _______________________________________________ Address messages to [email protected] No other addresses in TO and CC fields HELP: http://www.evdl.org/help/
