Jk BMS shut down and unable to restart

[Skypower]

No danger with the bms, it’s just an error in state of charge reporting. As far as I can tell everything else about it works, like balancing. It simply never gets to a harmful voltage. My solar assistant looks at the three batteries and averages the state of charge so now when I look at the dashboard I never see 100% even though it is. I ordered another bms, the same as the two that work and learn (24S) they are cheap enough to be considered disposable so I might even get one more. Just want the right data.
The voltage received at the batteries are all within .002mv with a 20 amp load and loss through the bms is equal so it’s swap out time in a few weeks. NBD!
Helicoils are a bit labor intensive and costly, from a production standpoint. The use is primarily repair of bad or wrong threads, improve thread longevity for repetitive use of fasteners in soft material like pure copper, aluminum(non-alloy) or plastic. It could be you have a more pure alloy(softer) that makes it easier and better to weld to the battery post which I know is very soft and low alloy. I’ve installed hundreds of Helicoils and Keenserts mostly the latter. But I prefer the Helicoils. They get a bad rap because the installer doesn’t knock out the tang or does it wrong. Omitting it leads to it peeling out or locking up the fastener. Just glad you didn’t use those short bolts. Grub screws/set screws are the way to go.

 

[fx99]

So it measures the voltage correctly and disables charging in time but simply shows the wrong SOC?

Regarding the helicoils, who knows, maybe they actually had a production mistake in a batch of cells and fixed them ?‍?

Just glad you didn’t use those short bolts. Grub screws/set screws are the way to go

I bet you have a good reason to say that, but I actually found it a bit annoying and even dangerous.
Am I right to assume that you can create a short circuit if you screw the grub screws on a negative terminal too far down and pierce through the probably pretty thin insulation layer onto the positively charged housing of the cell?
I tested how deep the grub screws need to screw in through the busbars and the balance lead cable shoes to be flush with the bottom of the terminal and then "glued" all the nuts onto the screws with loctite at the measured thread height.

 

[Skypower]

Am I right to assume that you can create a short circuit if you screw the grub screws on a negative terminal too far down and pierce through the probably pretty thin insulation layer onto the positively charged housing of the cell?

Uuuuh yeahhh!
But you’re a lot smarter than that and seen it coming! ??
I held the screws with a hex key till the nut snugged so it was at the hight where I wanted it. I was thinking of blue Loctite but figured it would be a pain if I took it apart in the future and wanted to give it a quick buff again. I don’t ever expect nor want the fastener to be part of the current carrier so glue or adhesive is cool on threads. I also don’t worry about the alloy of the fastener since it’s not going to be in a hostile environment. If I’m worried about galvanic corrosion I’ll put an anti oxidant at the junction to keep the air out, end of issue. The next bellevue washer I buy won’t be stainless. Three different brands and all loose 50% of the spring rate after the first use(soft/flattened). Real steel next time. Zinc plated nuts and washers work fine for home use and after a year, Zero signs of corrosion at disassembly. Some aluminums actually reacts worse with stainless. IMHO stainless is overrated. If I was to use other than stainless in a marine environment I’d just coat them marine “green grease” or NO-OX-ID A special and never worry about it.

 

[fx99]

That's crazy, I wonder if someone already managed to create a short that way.

I don’t ever expect nor want the fastener to be part of the current carrier so glue or adhesive is cool on threads. I also don’t worry about the alloy of the fastener since it’s not going to be in a hostile environment.

thats what I thought as well ? you're right though, if I want to take it apart again it's gonna be a pain with the loctite and the higher torque ?
But I really wanted it to be vibration prove, since I'm gonna install the battery in my motorhome truck.

If I was to use other than stainless in a marine environment I’d just coat them marine “green grease” or NO-OX-ID A special and never worry about it.

yeah nothing beats grease at corrosion protection. I had to restore the whole body of my truck and I'm definitely gonna give the entire chassis a coat of special grease on top soon so I never have to do all of that again ?