Either way is fine. Bms works fine with 20s.
Or you can buy one or two more.
Blew a hole? That doesn’t’t sound good. Or safe. What happened?
This sounds like it will make a good story…
Sorry, that should of said 72 volt GEM not 70.
Regarding the story, I hesitate to recount my stupidity, but in the interest of helping others …
I had cabled between my two boxes but hadn’t fished the BMS wires through yet. I decided it would be easier to fish the wires through the two boxes without the cable in the way. I disconnected only one end of the cable before I pulled it back out of the box and hit two batteries with the live cable. Just wasn’t thinking.
Inwo, I want to purchase two more batteries. How should I proceed? I believe I have your Venmo information. Thx Dan
So the cable touched on the cases of two cells and sparked? (making the holes?)
How bad? Show some pics.
That was 42 volts from the 12 battery case. So frustrating …
WTF? Aren’t the cases supposed to be dielectric material?
Wow! I think I will paint mine with bed liner or something!!
Maybe spray them with Plasti-dip?
No, the cases were not the problem. I pulled a live cable out the back of one box and through another touching the live end of the cable to the metal battery cases. Totally my mistake.
Understood that. I would have thought the cases were a bit better protected from a cable connector pass. It sounds like that stuff scratches through fairly easily.
Do you have anything else between your cell sandwich?
Maybe some of that thin countertop cutting board plastic?
(hard to tell from your pic)
“Maybe spray them with Plasti-dip?”
Separate with insulating paper. “Fish paper” or wrap with Kapyton tape like @djgabriel does.
Metal case is one of the poles of the battery, pretty sure is the positive so i kapton tape them and I use this kind of pad that goes under the tiles that is water proof (found it in Home Depot tiles section) Fish paper is also good
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" Metal case is one of the poles of the battery, pretty sure is the positive "
“Important safety tip there. Thanks Egon.”
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I finally hooked up and installed one of these in a local car this last Sunday.
@Inwo put this together few weeks ago and shipped it out to a guy here in my area named Evan.
It fit pretty nice. The hood closed.
This is FMB #1 - SDI 22s - JK BMS.
2002 e4+2(rear jumpseat)
R4F Blue motor (short) “Touched By Rodney”
Minor tweak in T2 Controller.
Main Battery Switch relocated up front.
First charge with the Stock Zivan charger (assuming wet profile- No dial selector) brought the pack up to 87.75 when the BMS shut the charge cycle down. We’ll watch to see if it is consistent.
I will go back and fab up a real hold down (instead of the ratchet strap).
Going to come back with a bar to mount the terminal posts so they aren’t floating.
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Looks nice!! Seems like the boxes were made to fit there!!
This is an amazing battery for pre 2005 cars.
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Byron does great work. 
If you are interested in building one, let me know. As of now I am unable to do another.
Demand is high for pre-2005 cars.
The boxes look like a good fit but that is a ‘wet’ compartment so water will get into those holes on the sides of the boxes. There is also nothing keeping the cables from moving so every bump and turn will be flexing the wire pigtails from the box exit to the cable attachments.
Maybe zip-ties to that green strap and then put some wide electrical tape over the box holes and pigtails down as far as the zip-ties?
Twice in the last month I had to slam on my brakes after two different jack-asses rolled through stop signs and then pulled out in front of me. After the first one I took a look at my battery under the rear seat and verified it had not moved. Even though they are not lead heavy, there’s a bunch of force on these hold-downs when we have to stop really really fast.