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Clarifying the title probably wouldn't hurt, but someone with more current knowledge than mine will probably give a more solid answer soon. There are Weber State videos that give great detail on the elements of the battery and how they are put together. It's been too long since I've watched them though and my memory is lousy, so I'm not sure about the difference between a section and a module. I think there are multiple sections per battery assembly, multiple modules per section and multiple cells per module.
The thing that surprised me about your service write-up is that the dealership actually serviced the internals of the battery assembly at all. I was under the impression that GM just shipped entire rebuilt battery assemblies whenever there are issues within the pack.
Thanks for posting your experience!
 

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I may have misinterpreted it. Check out the receipt I posted—does it mean that they replaced a single module?
I was actually more shocked that the dealer and service department were able to take out the battery and replace the section without replacing the whole battery as a whole. First time I’ve heard of that happening.
 

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Clarifying the title probably wouldn't hurt, but someone with more current knowledge than mine will probably give a more solid answer soon. There are Weber State videos that give great detail on the elements of the battery and how they are put together. It's been too long since I've watched them though and my memory is lousy, so I'm not sure about the difference between a section and a module. I think there are multiple sections per battery assembly, multiple modules per section and multiple cells per module.
The thing that surprised me about your service write-up is that the dealership actually serviced the internals of the battery assembly at all. I was under the impression that GM just shipped entire rebuilt battery assemblies whenever there are issues within the pack.
Thanks for posting your experience!
Yep! That’s exactly what prompted me to ask. Didn’t know that the dealer service departments were that technologically advanced already.
 

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Yes, many members here have had one battery module replaced at the dealer. Some Bolt-certified dealers don't have the equipment to do this.
Wish there was a list of dealers that Can't do this.... so we could go there and have a REAL professional replace things correctly...
 

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Shall I edit title to say Section instead of Module? I don’t want to confuse people.
Sure. If you like. Module 8 WAS replaced. It lives under the feet of the driver side rear passenger. However, it is permanently attacked to Module 3, under the other rear passenger's feet. They are both in battery Section 3.
 

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Yes, many members here have had one battery module replaced at the dealer. Some Bolt-certified dealers don't have the equipment to do this.
You're absolutely right, I just scoured the forum and found well-documented examples (like OP's) that clearly describe section replacements. For some reason when I replied I only recalled the full-on battery replacements. I must've conflated this with the earlier events pre-software update - the ones that suddenly lost power while driving. Memory's getting wonky. I'm still pretty amazed that they are able to perform this work on a dealership level.
 

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I'm still pretty amazed that they are able to perform this work on a dealership level.
Yes, I think GM may be the only manufacturer I've heard of doing sub-pack maintenance at local shops. It's impressive also because they would have to train auto mechanics to work around 200 volt DC. With the newer "skateboard" designs like Hyundai E-GMP, VW MEB or GM Ultium, I think it would make sense to design so that the dealer could remove a bottom plate under the pack, then remove any one of the 8 (현대) or 10 (VW) or 12(GM) modules from below.

(then there's NIO which can swap-out the whole battery in 3 minutes, making on-the-car maintenance unnecessary)
 

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Yes, many members here have had one battery module replaced at the dealer. Some Bolt-certified dealers don't have the equipment to do this.
I remember IBM repair guys coming out and replacing components on circuit boards in early computer days. Eventually, they started replacing boards, then whole units.

Seems wasteful? Sure, but the labor cost is minimized, technical specialists in a factory can recondition units to be used as FRUs, and overall it is less costly and greater customer satisfaction to have faster resolutions.

EVs are still relatively new, if GM learns module level surgery is too costly vs factory reconditioning, and customer sat is improved by doing pack swaps, then that is the way things will go. Module replacement on large scales like the current recall may be too costly and time consuming to GM...we shall see.
 

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I remember IBM repair guys coming out and replacing components on circuit boards in early computer days. Eventually, they started replacing boards, then whole units.

Seems wasteful? Sure, but the labor cost is minimized, technical specialists in a factory can recondition units to be used as FRUs, and overall it is less costly and greater customer satisfaction to have faster resolutions.

EVs are still relatively new, if GM learns module level surgery is too costly vs factory reconditioning, and customer sat is improved by doing pack swaps, then that is the way things will go. Module replacement on large scales like the current recall may be too costly and time consuming to GM...we shall see.
Yep, just swap out the entire vehicle and call it a day, GM! :D
 

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It will be interesting to see how battery serviceability plays out over the years.

The Tesla 18650 based battery in the Model S and X are serviceable, but I don't believe they service them at the service center.

The 2170 based battery in the Model 3 and Y are glued shut, you can't easily service them, they have to basically be remanufactured. Watch Sandy Munro's videos of the Model Y teardown or Rich Rebuilds' videos where the tear open a Model 3 battery and you'll see what I'm talking about. Tesla evidently decided that being able to service the battery locally isn't the approach they would take. If a battery needs work, it is replaced and the bad battery is sent back, like ARob's example about IBM.

The Bolt's battery can be serviced and they do it locally.

The Leaf's battery can be serviced and they do it locally.

I can't speak for other manufacturers because I don't know.

So currently it seems like most manufacturers design for local serviceability. Maybe we'll see this change as batteries get more robust and as the technology improves. Tesla seems to firmly believe in not servicing packs locally, and their structural battery design further shows this (although they claim that there will be ways to repair damage during a collision.) I'm guessing they made this decision based on data they saw for Model S and X batteries and how often they needed service. As Chevy gets more batteries under their belt, they may come to the same decision.

I'm conflicted about which approach I like most. I always try to fix what is broken before throwing something out. I like to be able to fix something. But I can appreciate the decision to build a pack that won't break in the first place, and in the remote cases when it does, send it back to be fixed at a facility that is equipped to do such things.

We're at the forefront of this revolution. In 20-30 years, if we still have batteries like we currently have, maybe one approach will have won out over the other.
 

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We're at the forefront of this revolution. In 20-30 years, if we still have batteries like we currently have, maybe one approach will have won out over the other.
In 20-30 years, we will either have much better batteries...or ox carts. I am betting on the oxen.
 

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I was actually more shocked that the dealer and service department were able to take out the battery and replace the section without replacing the whole battery as a whole. First time I’ve heard of that happening.
There are some videos online of them servicing Volts in this way. There are a lot of similarities in the process and equipment. I believe that the battery test unit is the same as the one that they use for both but the Bolt requires different adapter cables. The Bolt did build on the Volt more than many think.

I think that part of the issue is that there were so few problems they never really had an chance to get all that proficient.

You have to remember that the typical ICE vehicle is quite complex to troubleshoot. BEVs are not as much different as you might think.

"Glad" to see the info on the bad cell. It would be interesting to learn more about it.
 

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TE got it just right today. Politicians, and corporate heads, change beliefs like I change socks...whenever they start to smell.
And now Nissan has found religion again. Just like televangelists...you can always come back and ask for forgiveness. ;)

 

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[Edit: after a couple of drives and recharges, projected range was 250 miles this morning, with a max of about 290 and min of about 210. If this is in the real world ballpark I’m in good shape.]

My new to me certified pre-owned 2017 Bolt came with range problems. The dealer tech initially said there wasn’t a problem, but on further investigation caused, I think, by the recall, they found a bad cell and replaced that by replacing its module.I haven’t had it back long enough to know if the range is acceptable, but at least the battery has been thoroughly tested and “refurbished” (if you will). They also did the software update to limit charging. I’ve attached a photo of the receipt FYI.
View attachment 31963
We’re taught all our lives that batteries in an array should not be replaced individually. I wonder what’s so different about this scenario that now makes it permissible (except for $)
 

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We’re taught all our lives that batteries in an array should not be replaced individually. I wonder what’s so different about this scenario that now makes it permissible (except for $)
As with most things in life, there is more to it than that. Certainly $$ play a role in this but but it's definitely not the last word. Given the high level of battery management and monitoring the Bolt inherently has, I have a ton of confidence that GM with develop the proper improvements to deal with this.

What I expect out of this is better battery reporting that will preclude fires as well as better identify range issues. I'm still confident it could be pretty much a non issue with some minor software tweaks.

I'm sure GM is learning something here. They must deal with this sort of eventuality without having to resort to always having perfect cells. I have confidence that this will help make the breed stronger, safer and more reliable.
 
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