Hi Guys

I added a new Revov battery to my current 2 battery setup.

All seems well as al three batteries SOC when in use differs by 1-2% from each other. My question is on the new battery when fully charged cell 15 is at 3.6 and the rest at 3.3 (the other two batteries cells are all at 3.4)

The run light on the new battery stays lit and the battery SOC is 99.97% and varies slightly up and down. Is this the BMS balancing the cells? Over time cell 15 does come down.

How long do I leave it for it to balance properly or do I just use that batteries and it will sort it self out over time?

Thanks in advance.

 

 

Just to add just spoke to Revov and they said it will balance over time/cycles.

But told me to change the absorption and equalization from 55.5V to 55.0V is this correct?

 

Thanks

3 minutes ago, Zeus-JKR said:

But told me to change the absorption and equalization from 55.5V to 55.0V is this correct?

Yes, you don't want to go too high voltage wise, for the sake of cell life... higher voltage means shorter lifespan.  Is this a 15 cell or 16 cell pack? If it is 15 cell, then 55V is already too high, that would be 3.66666 Volt per cell, so I assume a 16 cell battery and that would then make the 55V a 3.4375Volt cell voltage which is fine, theoretically you could go up to 3.65Volt per cell (!!!don't!!!!), but between the 3.4-odd and the 3.6-odd Volt per cell, you probably find no more than 1 or 2 % capacity at a serious detriment to cell longevity.

Thanks Kalahari

This is 16 cell batteries. 

Do you agree that the cells will balance over time? Sorry I am still very new to this.

 

 

Edited February 28, 20242 yr by Zeus-JKR

3 hours ago, Zeus-JKR said:

Do you agree that the cells will balance over time? Sorry I am still very new to this.

I would imagine they would, but... the Revov were initially all 2nd life batteries as far as I know and if this is still the case, then your battery's cells have already a few thousand cycles behind them and should be betterer balanced by now, but if they are new cells, not 2nd life, then they may take a while... ideally you don't want a cell in the pack going quite this high/3.6V but that to a degree is also a function of the BMS... most of these crummy BMS use a resistor per cell to bleed off excess energy and this could take a while... every charging cycle...

Thank you so much for your advise and help

Not sure when Revov started with their batteries but 2.5yrs ago when I 1st saw them selling lithium their 2 x 12V versions had the one built with 2nd life and the other with new cells. Never looked at their 48V batteries. 

The best of both worlds. That was the time I bought my Hubble S-100 batteries that are using 2nd life. After over 2 yrs the S-100 is still showing a higher than spec Ah using my basic test method.