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Discussion Starter · #1 ·
My buddy's 2019 and my 2017 Premier both got the battery swap done in the last week.

Fully charged the range shows max 177 miles range.

Are they limiting the range by software?
 

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Probably still relearning. Drive the car normally for a few days.

When work is done on BMS software, it resets all history. It take a while for the car to relearn driving efficiency history which is a big part of the GOM estimates.
 

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Mine was showing 170 miles after the new battery was installed, even at 100% charge. I am not sure what the relearn reset actually does, but the GOM seems to be way off. I had to have some minor body damage repaired due to hitting some road debri, so I have not really used the car much with the new battery. I get it back from the shop today, so will see what happens. When I dropped it at the body shop it had 66% battery and was showing 128 miles of range.

I did notice some odd numbers on the kWh used and mile/KWh for the few days that I did drive it after the new battery. The kWh used read very low for the amount of battery percent used, as if it still thought I had my old degraded 51 kWh left. But it was giving me 5-6 mile/kWh efficiency, which cannot be correct.
 

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My buddy's 2019 and my 2017 Premier both got the battery swap done in the last week.

Fully charged the range shows max 177 miles range.

Are they limiting the range by software?
Technically? Yes. The software calculates your range based on your driving habits. Personally I like seeing a somewhat realistic estimate versus just always telling me the car has "259 miles when full"
 

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Technically? Yes. The software calculates your range based on your driving habits. Personally I like seeing a somewhat realistic estimate versus just always telling me the car has "259 miles when full"
I saw an article about cold weather impact on EV range. The study apparently used owners perceptions of range loss based on the car's estimated range, rather than actual performance which is more difficult to obtain.

Unsurprisingly, Tesla came out on top with the least amount of range loss. Why? Because apparently the GOM on Teslas resets to EPA rated Efficiency * kWh stored in the pack. So the tendency is, regardless of recent driving efficiency, temps, etc, the Tesla GOM always starts out after a full charge at a fixed range estimate. Many Tesla owners I know report 20-30% loss in real life in colder weather. So, like you, I prefer the more realistic estimate, but understanding what goes into the calculations helps with how much confidence I put in the estimate.

Back to the topic at hand. As many of us have already said, give it time. Sure, there is a remote possibility of the repair being done incorrectly, but the higher likelihood is, it will take time for the range estimates to normalize. Every SW update to the BMS resets history, so those of use with several updates under our belts have seen it happen. More recently, battery swaps initially required no SW updates, but then the new diagnostics arrived a month or so ago and are supposed to be flashed on all Bolts, pre swap with 80% limitation, post swap without the 80% limitation.
 

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I my experience (which is an outlier based on others on the forum) after my HPCM2 module was replaced it has taken about 5000 miles to be somewhat normal again. I am getting the software update today for my 2021 and I have not gotten a new battery pack yet. I would recommended doing several long drives (or series of drives) to go from high states of change (90-100%) to low states of charge (< 20%). After doing this 2-3 times your battery should have relearned the new battery pack's state of charge.
 

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I'm only seeing around 160 miles with my battery charged to 90%. I think the fact that it's winter right now if the overarching reason for the low GOM number.
 

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Discussion Starter · #9 ·
It's socal... not that cold unless it goes by calendar date lol.

My buddy has already put 1000 miles on his driving to work and back in the week since it was installed. 177 miles is what is shows.

He was going to take it back in but my replacement from 2 days ago shows the same exact number.
 

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Guys, the miles range on the GOM means nothing.

Get the reading how many kWh were used from the battery and then come back.

It is like saying I can do 250 miles between visits at the gas station. I have no clue how many gallons of petrol you poured...
 
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The GOM is not a good or reliable indication of battery health. Recording kWh consumed and initial SOC and ending SOC will allow you to estimate the battery capacity reliably. OBD2 can show you individual cell information.

Lastly, none of us knows the mathematics behind the GOM's predictions. It low balls predictions for me despite a long history of contradictory efficiency readings. Basically: Don't read too much into your GOM and only care more about your SOC and efficiency.
 

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My buddy's 2019 and my 2017 Premier both got the battery swap done in the last week.

Fully charged the range shows max 177 miles range.

Are they limiting the range by software?
In that image you posted, can you please show us the miles/kWh registered ?
This way the story will be a lot better understood. That's because the average miles / kWh or (in my case) kWh / 100 km tells the story of the GOM :

Here is why :
Car Plant Vehicle Motor vehicle Automotive design


As you can see, I used in average 24 kWh/100 km since the last reset of my GOM (2 days ago).
This means, for a baterry of 64 kWh (my new one), if I drive with the same consumtion average of 24 kWh/100 km, the GOM would show me 266 km to full charge.

But, the reality is that my GOM would show me today that I can get about 293 km. Why is that, 10% difference between what I calculate and what the GOM shows ?
Plant Output device Gadget Communication Device Audio equipment


Because the GOM bases it's prediction on things that are far more complicated than a simple ratio as I did.
Nevertheless, from my experience, on long drives, the GOM of the Bolt EV is the most accurate of all the EV I drove.
 

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Recording kWh consumed and initial SOC and ending SOC will allow you to estimate the battery capacity reliably. OBD2 can show you individual cell information.
Kind of hazy (nothing new there), but didn't I see somewhere that the PIDs in Torque might need to be updated after the battery upgrade???
Or did I imagine that?????
(Not finding anything, so maybe I imagined/misread that)...
 

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Kind of hazy (nothing new there), but didn't I see somewhere that the PIDs in Torque might need to be updated after the battery upgrade???
Or did I imagine that?????
(Not finding anything, so maybe I imagined/misread that)...
I guess you'd use some of the 2020+ PIDS. Good thing that Sean Graham fellow has documented both! They're documented in the same CSV IIRC.
 

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When I bought my Bolt with only 5 miles on the odometer, the car assumes a very low miles per kwh for the GOM. As it learns the actual miles per kwh from the driver's habit, this will update. I am averaging 5 miles per kwh.
 

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My buddy's 2019 and my 2017 Premier both got the battery swap done in the last week.

Fully charged the range shows max 177 miles range.

Are they limiting the range by software?
My car did the exact thing after the swap.
I went Joan Crawford on the dealership and they scrambled to see if there was a software inhibitor still on it.
I live in Kentucky and it was cold when my swap was complete.
We had a few days in December with 70-degree weather and the charge showed 259 miles.
It's been a month now and I've noticed a difference in the new battery with the updated chemistry.
It charges faster and depletes slower than the old battery.
I live near Cincinnati with LOTS of steep hills.
I think the software rebooted or an ONSTAR diagnostic may have reset the system after the swap.
I do wish since it has a thermal management system that when the temperature is too cold for the battery to charge fully, the thermal management system should warm the battery so it will always fully charge to 250.
That could be an easy software update.
 

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...the thermal management system should warm the battery so it will always fully charge to 250.
That could be an easy software update.
Once you've finished charging and start driving, where would the energy to warm up the battery come from? Where would the energy to warm up the cabin come from?
 

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My car did the exact thing after the swap.
I went Joan Crawford on the dealership and they scrambled to see if there was a software inhibitor still on it.
I live in Kentucky and it was cold when my swap was complete.
We had a few days in December with 70-degree weather and the charge showed 259 miles.
It's been a month now and I've noticed a difference in the new battery with the updated chemistry.
It charges faster and depletes slower than the old battery.
I live near Cincinnati with LOTS of steep hills.
I think the software rebooted or an ONSTAR diagnostic may have reset the system after the swap.
I do wish since it has a thermal management system that when the temperature is too cold for the battery to charge fully, the thermal management system should warm the battery so it will always fully charge to 250.
That could be an easy software update.
I’m right across the river from you and drive 40 miles into Kentucky everyday for work. I can confirm the existence of hills.
 

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The GOM is not a good or reliable indication of battery health. Recording kWh consumed and initial SOC and ending SOC will allow you to estimate the battery capacity reliably. OBD2 can show you individual cell information.

Lastly, none of us knows the mathematics behind the GOM's predictions. It low balls predictions for me despite a long history of contradictory efficiency readings. Basically: Don't read too much into your GOM and only care more about your SOC and efficiency.
I agree. The OBD2 reader is the way to go. Get some custom PIDs for the Bolt and it will tell you the state of your battery pack. (And so much more).
The image here shows a pack capacity of 52.4 kWh at 87.5% charge. 52.4/0.875 is pretty close to the 60kWh advertised capacity (old battery). I'm using Torque pro. Charge up, check your capacity, reset your trip odometer. Do your normal drive til the battery is low then check your capacity. Divide the distance you drove by the capacity you used and it will give you your actual mi/kWh (or the inverse for kWh/mi). You'll find it's quite different from the GOM, but it will be accurate.
 

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