Originally Posted by Erik Aa
I discharged my brand new Nosram VTEC SC4100UVH cells today after having charged them about 2000mAh 3 weeks ago (I'm trying to store them until the winter season starts). I first discharded them using a light bulb. When I afterwards put them on the LRP discharge tray to equalize them at 1.0 volts, one of the cells immediately started venting (sizzling sound and a small amount of liquid leaked out of the cell). I took them off the tray right away. Is this a common problem (that these cells vent when put on a discharge tray)? Is the cell damaged now? I later charged the pack and everything seems ok. How to avoid this problem? Thanks.
Does your light bulb have a voltage cutoff? Probably not. You should never discharge NiMH cells down to 0V, all decent dischargers have a cutoff in the region of 0.9V per cell.
A loss of electrolyte when venting will have decreased the performance of the cell, although it sounds like it has survived, it will not be at the same level as a new cell, or the rest of the pack.
It is very important to check the voltage of NiMH cells regularly, ideally before each charge, they self-discharge very rapidly and this causes a lot of problems.