Do I need multiple BMS' for 3 batteries in parallel?
- Thread starter bmtrirow
- Start date
Yes and no...
If you have for instance 3 batteries in a 4s config each series set would need it's own bms...
If you arranged the cells in parallel BEFORE you series them, you can use one bms, but the balance system will be slow to react to imbalance...
So, yes and no.
If you have for instance 3 batteries in a 4s config each series set would need it's own bms...
If you arranged the cells in parallel BEFORE you series them, you can use one bms, but the balance system will be slow to react to imbalance...
So, yes and no.
No.
He is arranging the packs in 8 banks, of 8s +8s then tying them together at the BMS... kinda sorta how I’d do it...
If you have individual cells, you can make a bank of cells paralleled together, then take the banks and arrange them in series...
jasonhc73
Cat herder, and dog toy tosser.
So basically do this.
Treat each S set as one battery and BMS that battery.
Then copy that setup to the other two S sets.
Finally connect all three in parallel.
Now you have a 4S3P battery, with all cells being BMSed, by 3 BMSs
I am about to do nearly the exact same thing with my BYD setup. But I will be 16S4P after the 4 BMS installed.
Treat each S set as one battery and BMS that battery.
Then copy that setup to the other two S sets.
Finally connect all three in parallel.
Now you have a 4S3P battery, with all cells being BMSed, by 3 BMSs
I am about to do nearly the exact same thing with my BYD setup. But I will be 16S4P after the 4 BMS installed.
Solarfun4jim
Solar seduced :-)
@Supervstech
So, in the case of a 2P16S setup, where cells are paralleled first, could you hook up 2 BMS's(one down either side of the pack) such that you get back to a faster 'reaction time' to the imbalance. Would one BMS, fight with the other, since they would both measure each twin paralleled cell pack in the series? They should both show the same figures for the cells, as they will both measure the same twin cell pairing, but each should supply its own balance current????
Opinion welcome.
Last edited:
I dont think that would work.
Solarfun4jim
Solar seduced :-)
Thanks Supervstech....every day is a learning day
KBWaldron
Solar Enthusiast
Any current sets of xS batteries can effectively have their cells paralleled with wires between their matching respective S lines. Then you can get away with one BMS.
Before doing this be sure each cell is already balanced with their respective cells in the other S sets. Otherwise you’ll see a high current while they balance.
Before doing this be sure each cell is already balanced with their respective cells in the other S sets. Otherwise you’ll see a high current while they balance.
Solarfun4jim
Solar seduced :-)
I wasnt looking to reduce the number of BMS's, i was looking to boost the amperage of the active cell balancing....but my idea was shot down ...lol.
Stupid Monkey
New Member
- Joined
- Dec 14, 2019
- Messages
- 193
Whats the advantage of that over 4P16S with 1 BMS? I've 24 cells incoming for 6P4S on 1 BMS have seen nothing in research to say that 4S6P would be superior? Except if maybe you were using old mismatched cells?
jasonhc73
Cat herder, and dog toy tosser.
If you P before S, you can't balance across P, just S.
The balancer sees the P as simply one cell.
In the end the last two connections are still just one big battery. Make your voltage first (S), then copy that to make your capacity(P).
Stupid Monkey
New Member
- Joined
- Dec 14, 2019
- Messages
- 193
But do you need to balance across P?
Volts will balance themselves, and thats the issue, even with used cells with mis-matched capacity they'll balance volts and deliver differing capacity without issue?
Or am I missing something?
Volts will balance themselves, and thats the issue, even with used cells with mis-matched capacity they'll balance volts and deliver differing capacity without issue?
Or am I missing something?
KBWaldron
Solar Enthusiast
Yes, but the P cells are balanced within themselves. Thus all cells are balanced.
Similar threads
