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I have had my Bolt for a few months. I have my settings at 80% for charging. Repeatedly, the battery says it is done charging at 78%.
Is there something wrong with my car or is it just the way it is. I have checked the app on my phone as well as the MyChevrolet site and they both will say 78%.

Any insight a member can provide some info on this one will be super helpful

Thank you.
 

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I asked the same question when I got mine. I have mine set to 80% and every time I charge it, it says charge completed: 83%. I asked why it couldn't just stop at 80%. The answer I got here is that the percent charge is an estimation and being able to estimate the charge of the battery while charging versus after the charge is complete involves a bit of guesswork. I guess it's kinda like filling a 5 gallon bucket with a fire hose and trying to stop at a certain line drawn on the side of the bucket.

Mike
 

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Lol. Yeah, you are correct. Would rather they not lie. Wanted to validate there wasn't an issue that needed to be addressed.
I'd be happy if they simply matched the percentage shown in the Chevy app with what you set for the charge cutoff. I don't know why they can't do that. Obviously they are using inconsistent calculations between the Chevy app and the car's chosen cutoff. Just make them the same!

Mike
 

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I was wondering the same thing. We don't drive far on a daily basis, so I have it set to charge to 60% at home, and if I'm out and use a free charger, it is set to go up to 80%.
I have read that lithium batteries are happiest at 50% charge, and that storing them at a full charge is very bad, especially when they are hot. So, I elected the 60% level, and with a full day of running around, it might get into the mid 40% range, so not too much discharge the battery either. Last year, in preparation for a full EV upgrade from out PHEV, we installed an air conditioner in the garage which can get it down to 84 degrees in there in the middle of summer on 115 degree days.
Anyway, when I check the app, it always shows the battery at 58% when charging is complete. I am glad to know it isn't a problem. BTW, is there any screen on the car the shows an actual battery charge as a percentage? I am so used to my CMax showing the battery % on the center screen and totally false miles of range on the instrument cluster. (Always showed 21 miles range when the best it would get was 14 !)
I know the Bolt has the bars of 5% increments, but would really appreciate a number!
 

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A battery's state of charge (SoC) is estimated based on the cells' voltage. So the charging circuit goes for a certain voltage number that it thinks it'll be equivalent to the requested level of SoC as it charges the battery and cuts off when that is reached. But when the cells stabilize after the cut-off, the voltage may actually fluctuate a bit and the SoC value shift accordingly. You may notice a similar thing after you drive long distance, as the GOM's estimated drivable range may change somewhat between when you just pulled into parking and after you come back to the car a couple of hours later.
 

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I was wondering the same thing. We don't drive far on a daily basis, so I have it set to charge to 60% at home, and if I'm out and use a free charger, it is set to go up to 80%.
I have read that lithium batteries are happiest at 50% charge, and that storing them at a full charge is very bad, especially when they are hot. So, I elected the 60% level, and with a full day of running around, it might get into the mid 40% range, so not too much discharge the battery either. Last year, in preparation for a full EV upgrade from out PHEV, we installed an air conditioner in the garage which can get it down to 84 degrees in there in the middle of summer on 115 degree days.
Anyway, when I check the app, it always shows the battery at 58% when charging is complete. I am glad to know it isn't a problem. BTW, is there any screen on the car the shows an actual battery charge as a percentage? I am so used to my CMax showing the battery % on the center screen and totally false miles of range on the instrument cluster. (Always showed 21 miles range when the best it would get was 14 !)
I know the Bolt has the bars of 5% increments, but would really appreciate a number!
I set my target so that I end the day at about 40%. Currently, that looks like 52% (midpoint plus 1 bar).
 

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The my Chevy app will show you the percentage if you open it up in car play. (I assume android auto too)
 

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Hi, I have had my leased 2017 Bolt for almost 3 years now. During that time, I have always charged it to 100%, wanting to get the maximum possible range. As far as I can tell, doing this has not affected / hurt the battery at all. I've kept pretty good records and can show you how in the summer months, I have been able to charge to over 300 miles some days. Of course, in the cold MA winter, it maxes out at about 175 miles.
So, I've been very happy with my Bolt and intend to lease another one this summer.
1584570740827.jpeg
 

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I know in development, we charge to 75% and can see some stabilization happening where you can see the actual charge settles higher then first reported. Could be how they have it setup.
 

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I am always using the MyChevrolet app to know the exact SOC of the battery. I charge my Bolt EV up to "90%" SOC (assuming that every block = 5% of SOC) but instead it's always 88%. As you all see, there is a pattern : 88% instead of 90%, 78% instead of 80%, 58% instead of 60% SOC. I think it's all about the buffer of 2% that the Bolt EV battery has as a built-in security. This is also the case why always charging at 100% does not have an impact on the battery.
 

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I am always using the MyChevrolet app to know the exact SOC of the battery. I charge my Bolt EV up to "90%" SOC (assuming that every block = 5% of SOC) but instead it's always 88%. As you all see, there is a pattern : 88% instead of 90%, 78% instead of 80%, 58% instead of 60% SOC. I think it's all about the buffer of 2% that the Bolt EV battery has as a built-in security. This is also the case why always charging at 100% does not have an impact on the battery.
I don't believe the fact that partial charge does not land on a 5% increment implies what you think it does.

Here are two different Bolts at 100% DIC (dashboard/app), as seen on Torque Pro.

12-29-18-1.jpg used 2017 12,092 miles.jpg

Here is our Bolt at "hilltop", 18 bars. Hilltop varies by 1-2%

hilltop reserve.jpg
 

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A battery's state of charge (SoC) is estimated based on the cells' voltage. So the charging circuit goes for a certain voltage number that it thinks it'll be equivalent to the requested level of SoC as it charges the battery and cuts off when that is reached. But when the cells stabilize after the cut-off, the voltage may actually fluctuate a bit and the SoC value shift accordingly. You may notice a similar thing after you drive long distance, as the GOM's estimated drivable range may change somewhat between when you just pulled into parking and after you come back to the car a couple of hours later.
I've heard this before but I don't believe it. Why? Because I can open the Chevy app and watch mine charge and when I have mine set to stop at 80%, it will say 80%, 81%, 82%, 83% while charging. And it doesn't stop until it gets to 83%. After that, it stays at 83%. So there's no excuse why it just can't stop at 80%.

Mike
 

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I've heard this before but I don't believe it. Why? Because I can open the Chevy app and watch mine charge and when I have mine set to stop at 80%, it will say 80%, 81%, 82%, 83% while charging. And it doesn't stop until it gets to 83%. After that, it stays at 83%. So there's no excuse why it just can't stop at 80%.

Mike
Ah, so it's a different issue. The software is dumb, then.
 

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Ah, so it's a different issue. The software is dumb, then.
Seems like it. To be clear, it's not something I worry about at all. It would just be nice if the charging system and the Chevy app used the same calculation for battery charge. Then it wouldn't cause confusion for new owners.

Mike
 

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I don't believe the fact that partial charge does not land on a 5% increment implies what you think it does.
Here are two different Bolts at 100% DIC (dashboard/app), as seen on Torque Pro.
Here is our Bolt at "hilltop", 18 bars. Hilltop varies by 1-2%
From what I see in your pics, the 100% SOC is 100% in the app too. The Hilltop reserve (2017-2018) is about 88% SOC (Torque shows 88-89%) which equals my setup of 2 increments below max and the app shows me 88% too. I am not sure where I am wrong. Yes, the battery 100% SOC shows both in Torque and MyChevrolet app. Hilltop reserve and my setup of 2 increments down are the same - 88% SOC.
 

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From what I see in your pics, the 100% SOC is 100% in the app too. The Hilltop reserve (2017-2018) is about 88% SOC (Torque shows 88-89%) which equals my setup of 2 increments below max and the app shows me 88% too. I am not sure where I am wrong. Yes, the battery 100% SOC shows both in Torque and MyChevrolet app. Hilltop reserve and my setup of 2 increments down are the same - 88% SOC.
They call 20 bars 100%, but the SoC raw buffer is closer to 4% than to 2%. If they call 20 bars 100%, why wouldn't they call 18 bars 90%, and leave the Soc raw buffer at 88-89%?
 
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