Daly BMS balancing with no active charge

[KLandos]

Hey there,

I’ve found a couple of equal threads but not with a solution, that’s why I’m asking.

I have 2 16s lifepo batteries in parallel.

Due to storage space on the boat they are separated in 2 packs, each with it’s own Daly BMS.
One pack with 16s2p one with 16s3p 280Ah Eve cells.
All cells has been top balanced before installation and everything has been fine for the last months.
The problem is that in one pack one cell drifts off.
The absorption phase is way too short for the little balance current that the Daly offers to get this right.
The Daly support does not answer.
Is there any way to active the balancing without charge current?
The charging voltage (absorb) is set to 56Volt. Chargers are a couple of Victron mppts. Just the time above 3,4V but below 3,5V Cell / 56 V pack Voltage is too short.

Hope for any hints, if it’s not possible to configure the active balancers should help, no?

Regards!

 

[floydR]

Lower your cell voltage to 3.45V. (55.2V) if that solves it good. if not go to 3.4V. (54.4V)
Frequently one cell will climb faster when above 3.4V than the rest. Find when the cell starts to increase voltage faster than the rest. Use that voltage as your max cell voltage.
Also You could start the balancing at a lower voltage if possible with the Daly
later floyd

 

[KLandos]

Lowering the absorb voltage would shorten the balance time even more to maybe only minutes.
On a long view that will be not a good idea, not?
I’ve read that Balancing at the 3.3’s voltage range is a bad idea. Isn’t that true anymore?
Attached a picture. More or less 15min till the balance stop due to no charge current flowing.

 

[100kwh-hunter]

16s eve 280ah packs

DALY will not balance as you would like.
They only balance at a set V and if the cells are drifting more (in my case) than 0,80v.
I would go to your old settings and get yourself a heltec active balancer, for each bank one.
Those balancers can have a switch solderd on, for on/off.
One time in the month i run them for a night and that is it.
Not even neccercery, but that 0.01v difference.

Leave the balancer on as long as needed, they can do 5a on 16s, daly can do 1a on 2s, and that is the weak point of daly.

This works well for a lot of people, incl me.
I get full loads.

I hope this was helpfull, with best regards Igor