BMS cutoff happening?

[740GLE]

Bummer When the BMS kicked off at 13.8v was it still taking high current?

Ampertime or Chins has had decent reputation, but with anything that can come and go.

Another good brand is SOK but at that point price is starting to climb.

 

[edfardos]

Bummer When the BMS kicked off at 13.8v was it still taking high current?

No, maybe half an amp iirc.

Ampertime or Chins has had decent reputation, but with anything that can come and go.

Great, thanks, I'll take a look at these.

Another good brand is SOK but at that point price is starting to climb.

Yah, and they're out of stock everywhere?


I may just get a solar charge controller (Victron?) that has a configurable peak voltage and accept that cheap(er) lifepo's are out of balance, and will never accept 14.2V across their posts. I'll see if I can get the Victron/mppt RF interference under control with chokes.

 

[edfardos]

Following up, Returned Weize battery, purchased AmpereTime battery. AmpereTime battery BMS disconnects towards the end of the charge also. It's not as severe, in fact, if the charger lowers the current (constant voltage), it seems to work. If the voltage dips suddenly, the charger applies full current, and the BMS trips. Voltage settles, then low-current mode, eventually the BMS-trip cycle stops.

Once the battery is full, after resting, I apply 100mA, and the BMS trips at 14.03V.

I connected it to a 13.88V ham radio switching power supply, will leave it there for a few days. I guess the BMS will trickle out high sells through little resistors to balance at that voltage?

 

[740GLE]

So you think it is your set up not faulty wheezy or ampertimes?

Slamming the current into batteries as the voltage hits the knee is never good at preventing that rouge cell from tripping high voltage disconnect