The photos have a D140, red waterproof bms, and a smartbms. Ignore the subliminal 13s message 
The red ones are all over aliexpress. The PH pisses me off, but the bms is really small.
I found the 13s, but do not see the 12s Liion only wrong voltage. Well I can always use the 13s fro 12s. What wrong with the PH?
I searched for “12s waterproof bms”, there are TONs. EDIT maybe not tons
I always make custom balance leads, and crimping PH for me has very very low success rate, and prone to break. So I’m more likely to use inline splices for these things, which I also don’t like.
1 Like
It’s for Lifepo4 it will allow charging up to 43V. Is this one the 13s? https://www.aliexpress.com/item/13S-48V-16A-18A-25A-35A-45A-60A-Lithium-Battery-Protection-Board-BMS-Waterproof-with-Balance/32840499915.html?spm=a2g0o.cart.99999999.380.50263c00OfoDLx I knoe it will balance 12s as well but over charge protection won’t work right? My question is, since the bms balances once they reach the full charge, would it work as well?
Also these can be ordered without enclosures to be even smaller
do you know one that will work with 12s Liion cells? Only balacing and overcharge needed. Thx
Wow you’re right I’m shocked that there’s no 12s li-ion 42v option. 
probably ebike jump to 13s. the problem with 13s is that they might not balance actually loosing the all point of the story. In my understanding the balacing starts when the bms detects the max voltage and a 12s battery with 13s bms won’t reach it. Or is the max voltage for each cells?
1 Like
These are kinda weird bmss, if batteries do get out of more 0.1v drift the bms wont be able to balance it out, but that shouldnt happen anyways
They have 13s, just send them a message on aliexpress heres a link to 12s
The 12s is not for the right voltage. What should I ask to the seller? Sorry didn’t understand your point.
EDIT: Ah I see it now. You said to asked them if they have the Liion version of the 12s. Right? It’s indeed showed in the pictures but not in the specs.
Daly 12S 15A 25A 35A 45A 60A Waterproof BMS For Lifepo4 Battery With Same Port or Separate Port for lithium battery
Model: DL12S (3.2V Rated LiFePO4 battery bms not for 3.7V rated Li-ION Battery bms)
common Version : common port for charge/discharge
separate Version : separate port for charge/discharge
We can customize any PCB from 1S to 30S lithium batteries with different current.
I’m with you, get 12s bms for 12s pack. None of the mfgs documents the behavior or their bms so it’s a gamble.
It’s really strange, they have every variety, and every series count but 12. I’m thinking they’re out of stock?
no I checked in the past as well never found the 12s. 10s, 13s always present. My question is if the 13s will balance the 12s battery since you won’t reach the max voltage of the total package or is the max voltage on a single cells? In the latest case it should work.
The “one-port 25A” option seems like the one.
As @acido said they have tiny balance current.
Your question about will 13s bms balance 12s packs, I think the answer would have to be verified for every bms model.
1 Like
They can program the bms to be for li ion just send them a message
I already bought some 12s for li ion from them
2 Likes
I just send them a message asking what they can do. I will also look on ALibaba. I have a parcel leaving China anyway. Maybe I can drop it inside so that goes faster.
OK perfect. How did you measure the thiny balancing current? is 0.1V for each cells or the whole pack?
I didnt do any measuring on them
Like if you somehow have 11 p packs on 4.2 and 12th pack is at 4.0 this bms wont be able to balance it to 4.2
1 Like
You can also ask them for unpotted no enclosure?
Doesn’t every BMS feel this way?
ah ok so is for each p group. Then a 13s bms should also balance a 12s battery right? In case I can get the 13s version that is available. Does Bestech balance more’ I have D140 for a while and my battery seems doing fine.
Not sure, talking with chineese people with low english skills is pain in the ass
Im about to order these with no enclosure, Im planning on potting them myself
4 Likes