Show me your JK BMS mounting solutions

[OffGridForGood]

Why can't the balancer do this?

If i lived long enough!
LOL
Actually the balancer will never do it, if the runner hits high voltage cut off, and shuts down charging, then the BMS never has the time it needs to balance this cell. This really is the point of a careful top balance to begin with (yeah this pack I rushed skipped that step) initially

 

[Skypower]

If i lived long enough!
LOL
Actually the balancer will never do it, if the runner hits high voltage cut off, and shuts down charging, then the BMS never has the time it needs to balance this cell. This really is the point of a careful top balance to begin with (yeah this pack I rushed skipped that step) initially

My last battery build I didn’t top balance either, I just planed on letting the 2amp balance circuit handle it. Surprise! Yeah I could see that was going to take forever with OVPR trigging and recovering a hundred times even with a low charge rate. In the meantime my system would be off line till done. Bull stuff, I’m going to force this thing through for part of a day and git-er-done. So I played cell bop-a-mole pulling the high down with the resistance of 400’ 10awg roll and cranking up the lows with a 10 amp power supply. I do have a 100 amp 3.65volt power supply to top balance but that would have necessitated reorientation of the cells(buss bars issue) and I wasn’t about to un compress and re- compressed the cells afterwards.

 

[OffGridForGood]

My last battery build I didn’t top balance either, I just planed on letting the 2amp balance circuit handle it.

and in my case 0.6A balance current on a set of 304Ah cells..with one kinda extreme runner - was never going to work itself out!

An interesting side note: I ordered some 2A and 5A active balancers, but never needed to install them, once cell #11 was beaten into submission, the pack has never drifted off balance, it has been half a year since that 'bop-a-mole' day. LOL

 

[Skypower]

and in my case 0.6A balance current on a set of 304Ah cells..with one kinda extreme runner - was never going to work itself out!

Yeah, that would have been like fart fighting a cat 5 hurricane. 0.6 amps would never have overcome that much imbalance and if it could, holding the cells at that high state of for weeks waiting for something to happen, wouldn’t do the battery any good either.

 

[OffGridForGood]

Yeah, that would have been like fart fighting a cat 5 hurricane. 0.6 amps would never have overcome that much imbalance and if it could, holding the cells at that high state of for weeks waiting for something to happen, wouldn’t do the battery any good either.

yeah electroplating the crap out of all the other cells ! yikes after paying real money for these ?!
just shows though, a proper top balance in the first place would have solved this issue, I mean I would never have even seen an issue,...ie like all the other packs LOL

 

[Zwy]

You guys do 16 cells in one long string?

 

[Zwy]

If i lived long enough!
LOL
Actually the balancer will never do it, if the runner hits high voltage cut off, and shuts down charging, then the BMS never has the time it needs to balance this cell. This really is the point of a careful top balance to begin with (yeah this pack I rushed skipped that step) initially

In my case I have a runner that as soon as charging stops, it drops in voltage quickly. The Batrium bypass holds it down below cell high voltage disconnect. It can still be high but once charging ceases it drops down below the other cells quickly.

The other cell that always lags just never gets any higher for voltage. It's a slow mover. I could use a power supply to bump it up, but it probably will revert back to lower voltage once the pack is drawn down to low SOC.

 

[Skypower]

View attachment 194656

Animal ! Lol

 

[Checkthisout]

View attachment 194656

Compression and you even got every single balance lead fused!

Very nice!

 

[Zwy]

Compression and you even got every single balance lead fused!

Very nice!

Batrium runs fused balance leads. It takes some time to wire these all up. I made the first harness in the shop, then copied it for the rest. I also drill and tap the busbars for the balance leads. I also use ferrules on the K9 balance lead connection.

I'm currently collecting everything to build another box for the shop. This one will use JK BMS's. The box has more room inside as it is deeper so might mount the BMS's inside.

 

[Hans Kroeger]

Test

 

[Hans Kroeger]

They have a place, usually low amperage AC. I would not run high current thru the Wago, but that isn't a concern with your application

• Simple and tool-free use thanks to the lever
• Convenient conductor connection from 0.2 to 4 mm²
• Stripping length: 12–14 mm
• Rated voltage: 450 V
• Rated current: 32 A

For a small wire like a balance lead, I can't see how it would have a good connection. For a critical component like a balance lead, I would not use a Wago

It is better to check resistance of a circuit using voltage drop under load. Resistance tests simply mean that a connection exists. The only thing an ohmmeter tells me is there is some type of continuity between 2 points.




It's simple, the ampacity will be much lower across a point of resistance with lower circuit voltage voltage. On a 16S pack, the voltage at cell 16 is 48V nominal, cell 1 will be 3.2V nominal. Apply Ohm's Law.

I measured the resistance as a Voltage drop of 7 mV at 10 Amps DC current.
Your explanation of ampacity versus circuit Voltage makes No Sense. The voltage at cell 16 ist 48V in ref. to ground. The Voltage across cell 16 ist only 3.2 V , the Same for all cells.

Can cell balance still be achieved? It can, but the time may increase and it may not be perfect balance. It would also depend on the balancer whether it is active or passive. The battery is charged to a set voltage point and that pack voltage is the sum of all series cell voltages. Some may be higher and some lower than average.

???

 

[740GLE]

The last time I did balance lead connection extensions I used non- insulated butt connectors using a crimper with fold in dies. Then covered with highest quality adhesive lined shrink tube. I can’t imagine a better low profile connection. I just don’t trust crimping insulated terminals and connectors, bad experiences. As for household wiring, I’ll stick to the old fashioned wire nuts that I’ve got more than a lifetime supply and I’ve never had a failure of any that I’ve installed. View attachment 194576

What’s your preferred ring terminal or cell connection for the balance leads?

 

[740GLE]

Not a JK but a JBD BMS. 3D printed enclosure.

You able to print a few more of those off and drop ship them? I like how it insulates the BMS.

 

[brb58]

You able to print a few more of those off and drop ship them? I like how it insulates the BMS.

I share the STL. Not really in the business of making things for other people.