Daly BMS CHG/BLNC issues.

[UnDa_KuVa]

Hi everyone.

I've been having issues with my Daly BMS ( no surprises)

At first it wouldn't balance my batteries out so 1 cell would be to high and turn off the CHG MOS. Spoke with Daly they suggested I get a balancer.

I bought a Daly 5A balancer put it on and it balanced them out and still does whilst the solar is switched off or the voltage coming in is lower than its specified for.

As soon as the full sun kicks in and the sum voltage rises, cell imbalance starts and the CHG MOS switches off yet my cells keep rising.

( Note: my battery percentage does not rise even when the CHG MOS is on my batteries are quite low now.)

Attached are some pics

*24v 150A Daly BMS
*24v 180Ah Sinopoly Cells
*5A Daly Active Balancer

 

[Daddy Tanuki]

the five amp "balancer" is set wrong so its literally unbalancing the cells. set the balancer to only come on above 3.4 / cell also set it to only work while charging.
set the stock passive balancer to only work at 3.65 (you are shutting it off for all intents and purposes) .

this should help keep it from unbalancing the pack. it will take longer to balance depending upon size of pack but still faster than the passive system and less chance of unbalancing it. you might need to top balance one time and start from scratch if you have one cell going nuts.

 

[RGUERI1]

I had the same issue on my 16S 48V LifePo4 battery pack. The Daly BMS has a passive balancing circuit which essentially just bleeds off the highest cell to the lower cells. However, in my situation I had to replace one cell and didn't top balance the whole pack when I made the swap. So the new cell would always turn the charge mosfet off while the other 15 cells were still not charged. Long story short, I busted all the cells apart and charged every cell individually to the same voltage and installed the daly active balancer. This did the trick and also allowed me to get the full capacity that I was expecting. It's worked perfectly since doing this and I can get an extra few miles out of the cart before needing a recharge. I never would have thought a 0.5V difference per cell would make that much of a difference.
I keep mine active all the time, not just while charging but that's due to the application being a golf cart and I don't have the charger plugged in all the time, like with a solar system.