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I've been collecting data for the past week since my update. Based on that data, my battery pack now only can charge to ~54 kWh. It was 60 kWh the day before the update. I'll continue to collect data, but everything points to the fix reducing the effective size of the battery (and consequent range) by 10% and relabeling it as 100%. It's not just ranting. The drop in range was immediate and very noticeable. My efficiency is irrelevant only the % of battery charge drop for the kWh expended. (My efficiency is exactly the same as it was before the fix 4.1 - 4.3 miles/kWh but the miles of range is down 10%.)
If you have the data from before and after, it might be worth contacting GM directly (not a dealership) about a buyback. I've read that GM started denying buybacks because the final fix restored 100%, but in your case, you can show that's not true.

You have to contact GM directly - use the concierge number 833-EV-CHEVY. What GM offers (if anything) may depend on the lemon laws in your state.
 

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2019 Chevy Bolt LT, Cajun Red
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I'm satisfied after looking at my data more closely, that despite the curve being different, the time to charge to 65-70% remains about the same. My initial fears about it being much slower have waned at this point.
I posted this is Wesley's thread, but will post it here as well and then move on.

35633


Keep in mind, these are kWh pulled from the EA unit, not delivered to the battery. One may probably estimate 10% losses if you truly wanted to know how many kWh made it into the actual battery.
My usable battery is around 55kWh fyi.
 

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I've been collecting data for the past week since my update. Based on that data, my battery pack now only can charge to ~54 kWh. It was 60 kWh the day before the update. I'll continue to collect data, but everything points to the fix reducing the effective size of the battery (and consequent range) by 10% and relabeling it as 100%. It's not just ranting. The drop in range was immediate and very noticeable. My efficiency is irrelevant only the % of battery charge drop for the kWh expended. (My efficiency is exactly the same as it was before the fix 4.1 - 4.3 miles/kWh but the miles of range is down 10%.)
Interesting.
How have you been collecting this data? What's is your methodology? Good to know for comparison...
Can you post some screenshots/graphs/logs or whichever you are using?

It would be really valuable to this thread!

Thanx!
 

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If you have the data from before and after, it might be worth contacting GM directly (not a dealership) about a buyback. I've read that GM started denying buybacks because the final fix restored 100%, but in your case, you can show that's not true.

You have to contact GM directly - use the concierge number 833-EV-CHEVY. What GM offers (if anything) may depend on the lemon laws in your state.
... just know that GM will probably offer pack replacement instead of buy-back. I think new Buy-back is a no-go once the final fix was released.
 

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I've been collecting data for the past week since my update. Based on that data, my battery pack now only can charge to ~54 kWh. It was 60 kWh the day before the update. I'll continue to collect data, but everything points to the fix reducing the effective size of the battery (and consequent range) by 10% and relabeling it as 100%. It's not just ranting. The drop in range was immediate and very noticeable. My efficiency is irrelevant only the % of battery charge drop for the kWh expended. (My efficiency is exactly the same as it was before the fix 4.1 - 4.3 miles/kWh but the miles of range is down 10%.)
If your vehicle didn't have the original available update (that was done back in 2018) it's possible it was never calculating your range properly. That update changed the range to calculate capacity based off of the worst performing cell instead of taking an average. A slightly weak cell could still be within their replacement difference in voltage. If you can look at what the voltages of the cells are, 4.16V or slightly higher is a 100% charge. The 95% update limited it to 4.10V.

Either way, any of the updates forces the car to re-learn what the actual capacity of the battery is. It might take a few charge cycles to get an accurate number, especially if you don't use a large percentage of the pack before recharging.
 

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Discussion Starter · #26 ·

Guess which one of the three coolant pumps will wear out first? At least the 12 volt should keep topped up.

06-11-21 pump still running 3.5 hours after charging.jpg 06-11-21 still charging 12 volt 3.5 hours after charging.jpg
 

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Discussion Starter · #28 · (Edited)
@Telek,

A couple more things to report. I wondered if people who program their smart EVSE to shut off when it is done charging would miss out on the battery monitoring that continues for hours after the charge ends.

I saw somebody on here say that some folks had their Bolt shut down after charging to 100% with the new update. Supposedly the software detected a problem with their BECM, which then needed replacing. I figured I wanted to know if that was going to happen BEFORE we planned a big trip. So I switched from hilltop to full, and came back when it had finished. The EVSE was live, and the high power electronics pump was running to cool the onboard charger and the accessory battery charger, as it trickle charged the 12 volt to keep up with the computer load....just like the previous two charges since the update. I figured I'd burn off some of that charge going into town to look at the 2022 Bolts at the Chevy dealer.

I unplugged the charge cord, and was interested to see the trickle charging and pump continued running off the traction battery. So GM will monitor the battery even if you cut off wall power. I assume it contlines if you drive off with the car too.

Oh! I really like the frontend changes to the 2022. I know everybody has their own esthetic views, but I think it now looks like a real 21st century car.
 

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I don't think I've ever charged to 100%. Are we suppose to do that at some frequency for the new monitoring to work properly?
 

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Discussion Starter · #30 ·
I don't think I've ever charged to 100%. Are we suppose to do that at some frequency for the new monitoring to work properly?
The update bulletin said the car should be charged to 80% at least once after the update. The thing about it picking up faulty BECMs was from a forum member. I didn't see any link, so can't say for certain. But I figured better safe than sorry later.
 

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The update bulletin said the car should be charged to 80% at least once after the update. The thing about it picking up faulty BECMs was from a forum member. I didn't see any link, so can't say for certain. But I figured better safe than sorry later.
OK, dealership did not provide me instruction to do that but I guess that was too much to ask. Maybe it should be on the recall paperwork for customer to initial...
I guess I'll charge to 90% next week/weekend (that would be probably 87%, which is > 80%).
 

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Hey everyone,

My name is Kevin, and I run a YouTube channel called The Wrenching Fool. I've had my 2019 Bolt since November 2019 and document some of my experiences with it, as well as other car stuff on that channel. I used to have another account on here, but I can't seem to find it now...

I recently got the latest battery recall software update performed and just posted up a video comparing the 5-95% DC fast charging experience.

Hopefully linking is allowed, if not, just search YouTube for my channel name.

I've also put together some some graphs showing the difference in the charging curve, which are available in the description of the video linked above. They did in fact go to a more gradual curve like the 2020+ Bolts, but it still hits all the same taper points as it did before. In other words, it starts slowing down charging earlier in order to hit those taper points. They also seem to be much more aggressive about cooling the battery pack, as the AC compressor kicked on to start cooling the battery at about 88 deg F after the recall vs 102 deg F before the recall. This could be an issue in warmer climates if they always want to keep the battery below 88 deg F, because it means that the battery cooler is going to be running most of the summer if the rest of the cooling strategy is the same.

Regarding battery capacity, I can't be 100% sure yet, but it appears that the capacity may have been reduced, but it is too soon to tell. It could just be due to the BMS still needing to relearn the capacity, but my first range test after 2 days and a couple hundred miles of driving AFTER the recall was performed (as well as 2 100% charges) indicates that my pack capacity may be down to 59.8kWh AFTER the update compared to 61.1kWh BEFORE the update. More time and testing is needed to verify that, but the total energy needed for the fast charging experiences I compared in the video above seem to support that as well (60kWh required to charge 3-97% BEFORE the recall, 58kWh required to charge 2-96% AFTER the recall as per Electrify America).

I'll also be covering some more technical info on the recall from my perspective as an automotive technician in a future video at a future date.

Also, to respond to the comment that GM is no longer doing any buy-backs on Bolts now that a final "fix" has been released...I don't want to say too much, but I would say that if you are concerned about your 2017-2019 Bolt, especially if you are the original owner, definitely give the EV Concierge a call and inquire, because YMMV. More info on that in the future.
 

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@Telek,

A couple more things to report. I wondered if people who program their smart EVSE to shut off when it is done charging would miss out on the battery monitoring that continues for hours after the charge ends.

I saw somebody on here say that some folks had their Bolt shut down after charging to 100% with the new update. Supposedly the software detected a problem with their BECM, which then needed replacing. I figured I wanted to know if that was going to happen BEFORE we planned a big trip. So I switched from hilltop to full, and came back when it had finished. The EVSE was live, and the high power electronics pump was running to cool the onboard charger and the accessory battery charger, as it trickle charged the 12 volt to keep up with the computer load....just like the previous two charges since the update. I figured I'd burn off some of that charge going into town to look at the 2022 Bolts at the Chevy dealer.

I unplugged the charge cord, and was interested to see the trickle charging and pump continued running off the traction battery. So GM will monitor the battery even if you cut off wall power. I assume it contlines if you drive off with the car too.
The Bolt, and most EVs will continue to monitor the battery long after the vehicle is turned off and unplugged, because the battery has a limited safe range of temperature in which it can function properly. If it is an excessively hot day, the battery cooling will kick on even if the car is off when the battery temperature goes over a set threshold. That used to be about 102 deg F, but given that Chevy seems to be more aggressively cooling the battery now after the recall, it may be lower. It'll do the same thing for keeping the battery "warm." My 2019 will generally keep the battery somewhere above freezing and seems to shut off battery heating around 40 deg F. The point being that it will continue this monitoring and battery conditioning even if the car is off and not plugged in. It will also supposedly run the DC-DC converter to keep the 12V battery topped off as needed, but I have had my 12V battery go dead (within a month after buying the car new). It only happened one time, but still makes me question whether or not they actually do that (Chevy says that they do).
 

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I've been collecting data for the past week since my update. Based on that data, my battery pack now only can charge to ~54 kWh. It was 60 kWh the day before the update. I'll continue to collect data, but everything points to the fix reducing the effective size of the battery (and consequent range) by 10% and relabeling it as 100%. It's not just ranting. The drop in range was immediate and very noticeable. My efficiency is irrelevant only the % of battery charge drop for the kWh expended. (My efficiency is exactly the same as it was before the fix 4.1 - 4.3 miles/kWh but the miles of range is down 10%.)
Is there a drop in cell voltage at "100%" SoC when you compare pre and post update ?
 

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Discussion Starter · #35 ·
Is there a drop in cell voltage at "100%" SoC when you compare pre and post update ?
Not on ours.

It was charging at 400 volts right up to the end. Our highest cell said 4.181 volt, and the average said 4.165 volts, just like before. The voltages dropped a bit sooner after the charge. I attribute this to the new constant monitoring going on after the charge finishes. The new trickle charging mode doesn't perfectly match the computers energy use. Not a big deal. the next morning the average cell voltage was 0.001 volts lower than usual.

end of charge after the final fix.jpg 100% SoC after the final fix.jpg
 

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Discussion Starter · #36 ·
The Bolt, and most EVs will continue to monitor the battery long after the vehicle is turned off and unplugged, because the battery has a limited safe range of temperature in which it can function properly. If it is an excessively hot day, the battery cooling will kick on even if the car is off when the battery temperature goes over a set threshold. That used to be about 102 deg F, but given that Chevy seems to be more aggressively cooling the battery now after the recall, it may be lower. It'll do the same thing for keeping the battery "warm." My 2019 will generally keep the battery somewhere above freezing and seems to shut off battery heating around 40 deg F. The point being that it will continue this monitoring and battery conditioning even if the car is off and not plugged in. It will also supposedly run the DC-DC converter to keep the 12V battery topped off as needed, but I have had my 12V battery go dead (within a month after buying the car new). It only happened one time, but still makes me question whether or not they actually do that (Chevy says that they do).
The new monitoring is different than the monitoring I have seen over the last three years on Torque Pro. I am not talking about battery temperature conditioning. I am talking about continuous battery monitoring that goes on for four hours after the pack has finished charging, requiring the the 12 volt trickle charging that goes on for four hours after the pack stops charging.
 

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Discussion Starter · #37 ·
I recently got the latest battery recall software update performed and just posted up a video comparing the 5-95% DC fast charging experience.
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They also seem to be much more aggressive about cooling the battery pack, as the AC compressor kicked on to start cooling the battery at about 88 deg F after the recall vs 102 deg F before the recall. This could be an issue in warmer climates if they always want to keep the battery below 88 deg F, because it means that the battery cooler is going to be running most of the summer if the rest of the cooling strategy is the same.

Regarding battery capacity, I can't be 100% sure yet, but it appears that the capacity may have been reduced, but it is too soon to tell.
Watched the video. Good info. Thanks for posting.

Not at all surprised they are running the battery cooling more. Too bad they didn't do more testing before they came out with the Bolt. But they were determined to beat Tesla to be first with an "affordable" 200+ mile EV.

Torque Pro shows our Ah capacity actually going up a couple of tenths of an Ah after the final fix. Will do a full capacity drive sometime again this summer.
 

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The new monitoring is different than the monitoring I have seen over the last three years on Torque Pro. I am not talking about battery temperature conditioning. I am talking about continuous battery monitoring that goes on for four hours after the pack has finished charging, requiring the the 12 volt trickle charging that goes on for four hours after the pack stops charging.
I (and many others in the Korean forums) am seeing this as well. The charging session ended about 3 to 4 hours longer than previously expected in my case. Do you have any information (technical or official) that points out that it's the battery monitoring and diagnostics that's happening? I think some people are mistaking the behaviour for something that's broken.
 

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Discussion Starter · #40 ·
I (and many others in the Korean forums) am seeing this as well. The charging session ended about 3 to 4 hours longer than previously expected in my case. Do you have any information (technical or official) that points out that it's the battery monitoring and diagnostics that's happening? I think some people are mistaking the behaviour for something that's broken.
@Telek mentioned it 12 days ago, so I knew what I was seeing a week later, after having the update, and charging our Bolt.


Another forum member just posted a plot from his EVSE.

 
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