Vent released, and low amp draw?

[Bbbbrass]

I've started top balancing my 60AH LiitoKala cells, and one cell came slightly swollen, reading 2.58V, and the vent appears different from the others. Anything to be concerned about?

Also, any reason I can't pump more than 1.5amps into these cells?

Also, from the NOAH'S ARK link I think these might be ETC cells. Any thoughts?

 

[sunshine_eggo]

Typical reason. Cheap PS leads and the unit itself has high internal resistance. You've reached your 3.40V set point at the PS and are now voltage limited. Disconnect leads and increase PS supply to 3.6.

 

[Bbbbrass]

Thanks! Switching to good 8ga wire and instantly it went to 10amps. Even good new 12ga with proper ring terminals only allowed 5amp to flow.
Any worries about that vent being raised?

 

[sunshine_eggo]

Hard to say about the vent. I would keep an eye on that cell and see if it is a performance (less capacity) or physical (swells) outlier.

 

[Bbbbrass]

Update after 2.5 years. Pack hasn't been used much, and certainly not tested well. Capacity was lower than expected, Daly BMS is crap, and I didn't know what I was doing when I build this. Here is a picture of the swelling that has occurred. These cells have never been outside of voltage or C rating spec, and the one "vented" cell has an IR of 1.18, while the other 3 are all around 1.38. Going to drain them, compress them, balance them, and then see if they can be useful at all.

For new people who stumble on this;
don't get cells from LiitoKala
do compress prismatic cells
don't use Daly BMS
do really think about what you will need and use cells for before starting!

 

[Alkaline]

 

[Bbbbrass]

Yep, that video is more recent than when I purchased these, but if I had done a little more research, I would’ve found out they were worth even less less than the cheap amount I paid. I’ve done much better with the old Sinopoly cells.