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Can someone tell me what the best charging strategy is for prolonging the service life of a Bolt battery. I don't drive very far on a day to day basis so I have no need to ever charge up fully but I'm wondering if frequent partial charges is better or worse for longevity as opposed to infrequent charges to full, say once a week. I use only 120 volt charging. I know it 's not good to drain to zero which I never do, or to have the car sit for prolonged periods fully charged. It's the day to day short charges, say for 6 or 8 hours I'm curious about.
 

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Can someone tell me what the best charging strategy is for prolonging the service life of a Bolt battery. I don't drive very far on a day to day basis so I have no need to ever charge up fully but I'm wondering if frequent partial charges is better or worse for longevity as opposed to infrequent charges to full, say once a week. I use only 120 volt charging. I know it 's not good to drain to zero which I never do, or to have the car sit for prolonged periods fully charged. It's the day to day short charges, say for 6 or 8 hours I'm curious about.
Full charge and and full discharge can be bad for batteries, which is why the Volt limits the amount of its battery you can use.

In an effort to simulate this in my Bolt, I have set my car to use Hilltop Reserve for charging. This artificially prevents full charging, stopping about one bar shy of a full charge.

If I ever need the max range, I can temporarily remove the Hilltop Reserve limit. Otherwise, I simply charge the car every day so it's full (to the Hilltop limit) each morning
 

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Many opinions on this.

I've learned that Lithium batteries like being near the middle of their charge.
And to answer your specific question about little or lots at once, little is better, (you can stay nearer the middle)
Try to avoid long full charges on any lithium technology battery, but the Bolt is pretty well protected by GM's program.
So do what you will, don't be too concerned about it, the battery is likely to outlast the rest of the car.
Do charge it fully if you're planning a long drive, keep it close to half most the rest of the time, and it and you'll be happy.
 

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The Volt never lets the battery get above 80% SOC or below 20% SOC. That has garnered the Volt many hundreds of thousands miles with little to no battery degradation. If I had a Bolt, I would try to mimic that as much as possible.
 

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The number one thing you can do is put it in hilltop mode and leave it there. Only take it out when you really need to. I think just about everything else is "details," but the next thing I would do is just not bother to recharge it until it is below half. That will keep it at a lower state of charge, on average, which is better for longevity. There are also things you can do with the delayed charging settings to end the charge before full, if you want to set that up.
I think if you try to be much more fastidious than that, you will be putting more time and effort into managing it than it is worth.
 

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Doesn't the Bolt also keep a buffer when charging like the Volt?

If not, how do you set the Hilltop Reserve? I guess I have some manual reading to do.....

I have just become accustomed to plugging in both the Volt & Bolt at the end of the day.

Jim I - 2012 Volt & 2017 Bolt
 

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Doesn't the Bolt also keep a buffer when charging like the Volt?
Some, but not nearly as big. There's about 2-3kwh of buffer at each end in the Bolt, as near as I've been able to find. Hilltop doubles that at the top end, where it's really useful.
 

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Tthe next thing I would do is just not bother to recharge it until it is below half. That will keep it at a lower state of charge, on average, which is better for longevity.
No disagreement on that point from a technical perspective. From a usability perspective I want a full battery every day, especially in Winter. Cold weather cabin heat, snow/rain traction losses, unexpected hour or longer accident delays, and side trips are some of the reasons I want to be prepared with a full charge.

So for me it's a trade-off. I use my Volt the same way: it has a full charge every morning. Plus, filling half the Bolt's battery could take a while on my relatively meager 3 kW 240V setup. Someday I will look at upgrading the circuit wiring to support 7.2 kW, but that's a way's off.
 

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Everything said so far seems right. However, don't over-think it. GM engineering has designed a very good battery management system so that these concerns are pretty much unfounded.

One other point that I didn't see yet, it would probably be better to avoid DCFC if you can. Would not be good for longevity to fast-charge every day. Since it is an allowed behavior, though, the warranty would cover any excessive degradation.
 

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No disagreement on that point from a technical perspective. From a usability perspective I want a full battery every day, especially in Winter. Cold weather cabin heat, snow/rain traction losses, unexpected hour or longer accident delays, and side trips are some of the reasons I want to be prepared with a full charge.

So for me it's a trade-off. I use my Volt the same way: it has a full charge every morning. Plus, filling half the Bolt's battery could take a while on my relatively meager 3 kW 240V setup. Someday I will look at upgrading the circuit wiring to support 7.2 kW, but that's a way's off.
I agree with you, but the OP stated "I don't drive very far on a day to day basis," so my suggestion was based on that specific case. I would keep mine more on the full side for the reasons you stated.
 

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I don't own a Bolt but I can say without any doubt is that following whatever the owner's manual recommendations are is the path to long life for the batteries. The GM engineers know the systems better than any opinions you may get on this discussion board. They have tested the Bolt battery in ways that most "experts" haven't imagined. The Bolt is not "the same as" a Prius, or a Tesla, or any other manufacturers battery system.

Read and understand the info in the owner's manual, drive it as you see fit, and don't worry to much about the life of the batteries. I promise you will move on to something else long before there are any major issues to concern yourself with.

VIN # B0985
 

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.... The Bolt is not "the same as" a Prius, or a Tesla, or any other manufacturers battery system....
It's not? How so? It has TMS which is better than some, but other than that?
 

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It's not? How so? It has TMS which is better than some, but other than that?
I've worked in the field of vehicle evaluations at both GM and Toyota and I can say that GM's product testing and development is robust. Toyota targets to be above average while GM's target is to satisfy the 95th percentile customer. Tesla's approach seems to be to build the product, sell it to the customer, then fix problems as they arise making the customer fleet their testing fleet.

My vote is for GM's approach.

VIN # B0985
 
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