The battery builders club

@Acido so you’ve used the silicon repair tape to insulate your battery?does it work,?

When my cells get damaged i use the 18650 cell shrinkwrap

No, I have never used that tape or any tape to insulate my cells

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Ahh i think i misread your post thanks anyways i pretty much decided to wait for the fishpaper (dont really feal like being the one to try that stuff for science) :+1:

just stumbled on this last night, active cell balancers. unlike bms, which bleeds off excess charge via resistors at full charge, these things transfer charge from cell to cell if it detects drift beyond 0.1v. and it does it at a pretty high rate of 1a.

https://www.youtube.com/results?search_query=active+battery+balancer

immediately ordered one to test.

has anyone used one of these before?

i really want to stop using bms’ - they’re so goddamned finicky.

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I’ve ordered one as well. I’ve got a 12s6p Im building currently, hopefully this will get here in time to test on this pack.

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I ordered one 6s and 13s as well. I think soon we get some good information about them :sweat_smile:

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oh shit, there’s a post. sorry, should have searched.

anyway, let’s see how it goes.

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No problem. It’s good that we have this in this thread as well.

Awesome. Thought they were more expensive. What u think of skipping the bms and just using this

@KfromtheBay @ducktaperules wouldn’t he have been fine if he’d had the fuse put on the side with the battery in the diagram above. And that would’ve disconnected and not rely on the individual cell fuses. All the cell fuses seem a risk if they were to break off in the battery and float around

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Why no 10s on these active balancing boards :joy:

Do ten on the twelve

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if you ask the chineese will make it :smiley:

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You can just skip the ports you don’t need. That’s what as min the supplier said. So 13s work for everything below that.

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Oh I like this Idea :astonished:

right, my understanding is unlike a bms that needs total pack voltage to start balancing, these balancers are looking strictly at each cell’s voltage. that’s why it works for all chemistries.

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So, I’ve built a few batteries, all with a BMS. Im finding it difficult to decide if this cell balancer should be on while charging directly to a packs pos & neg leads or charge to 80% and then turn it on/connect it. Any ideas?

not sure, i don’t have nearly enough experience to even guess.

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me either, I guess we will figure it out :slight_smile:.

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You have this balance board always connected to the balance leads. No connection to the main leads. As long as the packs are in balance (i think it’s ±0.03V) the board is switched off. As soon as one pack gets out of this tolerance it will switch on. There are small indicator leds on the pcb which will indicate if it’s on or off.

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It just compare the voltage difference between the parallel packs. As soon as one get out of balance it start shifting the energy from the pack with the highest voltage to the other packs. In fact it doesn’t matter which chemistry it is in this case. The main down side on that board is that there is no overcharge or overdischarge protection. For this you would need to add a bms again.

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