Since your pack is already perfectly balanced If I was you I wouldn’t even use the active balancer. Just let the bluetooth BMS keep the pack balanced.
My cells are known heavily-used and abused cells they are not new like yours likely are.
And I also purposely started them out unbalanced to test this balance board.
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However this balance board clearly caused them to drain unevenly. As soon as I unplugged the balance board it stopped draining so jurassticly.
Luckily the AliExpress seller seems to be open to sending me a new unit (which he should…). I’ll let you guys know if the new unit works better and I just got screwed with a bunk unit
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@Flasher i think you missed out the part where @Fiori add the active balancer to his pack in addition to the smart bms.
the drain was caused by the active balancer and not by the smart bms as far as i understood as min.
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I’ve manually balanced them fairly close. I’ve now reconnected the active balancer and it seems like it’s opened up the 5-6 circuit. I wonder if it won’t open circuits that are too far apart (what’s the point then??).
I’ll see if it will balance them out now. I also turned active balance back on on the smart BMS because it can’t hurt.
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Maybe try different active balancer? For me this cheap one works really well. Try unplugging balance wires from the bms. Just a thought.
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Are you telling me you just built a battery in 15 hours?!?! Holy shit, you must be crazy then 
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After you’ve done so many of them it goes pretty quick. I already have 2p, 3p, and 5p jigs made up for aligning the cells. I actually did a 12s3p start to finish, and got about 60% done on a 10s3p in the same day.
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once i get into, i can get a pack built in about 3 hrs. only thing that takes time is curing silicone adhesive. that and testing, that takes a while too.
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Geezzz… you guys are crazy. I keep telling myself the reason it literally took weeks for me to build my battery is because of all the testing and things not working lol…
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Look what I happened to stumble upon:
http://www.bestechpower.com/balanceboard/D172.html
Looks kind of promising:
Sounds to me this just does the balancing function in a bms, at a higher balancing current (higher current resistors?), and forgoes all the protection circuitry.
Still asking questions, gonna order some and see.
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Do you really need higher balance currents? Mine does 60mA and I set it to start balancing at 4v. When it reaches full it looks pretty good. Waiting for it to reach 4.2 before starting feels to me like you’re extending the time it takes. I can ofcourse be completely wrong 
last night’s charge was perfect 
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Because most people don’t test and match cell mAh your pgroups are bound to age slightly differently and need more balancing as you get more cycles on the battery.
There’s a “new” ANTBMS that supports 200mA balance current and up to 320Amp (yeah right) discharge.
Not to mention it supports anything from a 6s to 24s battery, haven’t tested it too much yet but results are promising compared to the xiaoxiang BMS ones.
Also it’s like the perfect size for a discharge BMS and supports active balancing got a precharge circuit and many other goodies I haven’t discovered yet I’m sure. C$ 70.75 25%OFF | Smart 7S ~ 20S ANT Lifepo4 li-ion Lipo LTO Battery Protection Board BMS 400A 300A 100A 80A Bluetooth APP 10S 13S 14S 16S Balance
https://s.click.aliexpress.com/e/KA7LieMdV
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Definitely interesting. Kne point I noticed though is that in the item description it only states 100ma of balancing
It comes preset to 150mA and supports between 50-200 on the app. The bleed resistors are connected to the heatsink so it should be fine.
AliExpress descriptions are a 50/50 50% of the time it’s what they say, 50% of the time it’s worse shit and the other 50% of the time it’s way better than listed.
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