Important to put an insulator between the cells preferably epoxy fibreglass sheet as the casings are live and the thin blue plastic is not enough to be a reliable insulator
We highly recommend it. We have observed cells slowly start to expand as soon as they crossed above 3.4v and after discharge they did not return to their original size
On the EVE 280ah cells they say 300Kgf. Does that mean i take that much force and just torque the pack down on one side with 4 nuts? Hear about people using springs but im unsure about the optimum solution
After top balancing to 3.65v in parallel, the cells are re-configured in series 12v, as they would be in normal use. They are drained so that the internal stresses that would cause cell expansion are relieved In this case, we do it with the long bars so that the pack can be re-fixtured in the proper positive/negative orientation. De-compressing the pack at 100% state of charge would result in the cells swelling up / bloating nearly instantly.
Finally someone that knows how to proper compression!
Important to put an insulator between the cells preferably epoxy fibreglass sheet as the casings are live and the thin blue plastic is not enough to be a reliable insulator
Maby add some kind of sticky paper to protect the cells from the iron rods ore a small plastic plate
Excellent video !!! Please make more !!!
Do you really NEED to compress them before you top balance? Especially if it's a really low C rate?
We highly recommend it. We have observed cells slowly start to expand as soon as they crossed above 3.4v and after discharge they did not return to their original size
On the EVE 280ah cells they say 300Kgf. Does that mean i take that much force and just torque the pack down on one side with 4 nuts? Hear about people using springs but im unsure about the optimum solution
Is there any reason I cant use plywood instead of the plastic?
Strength and moisture retention, but a lot of DIYers opt to use plywood anyway.
@Current Connected Drain to 30% SOC? That's bottom-balancing? I haven't seen anyone talk about bottom-balancing -- only top-balancing.
After top balancing to 3.65v in parallel, the cells are re-configured in series 12v, as they would be in normal use. They are drained so that the internal stresses that would cause cell expansion are relieved In this case, we do it with the long bars so that the pack can be re-fixtured in the proper positive/negative orientation. De-compressing the pack at 100% state of charge would result in the cells swelling up / bloating nearly instantly.