Originally posted by Java1970
Stick packs are notorious for having a "dead" or "vented" cell. The one pack I saw do the same thing, was charged the first time over the recommended charge rate (about 3 amps for NiHm, 4.5 amps for NiCd max!!!) and had been over discharged after the run. Most chargers are set to auto detect the proper amprage for charging, the adjustible ones should have the recommended range on the face or in the manual. Contact the manufacturer of the battery to be certain, but charging it at 6 amps is double the recommended rate and probably ruined the cells.
If these are GP3300 cells, we reccomend charging at 6 amps. A 3 amp charge would give you very flat cells for a long run time. That's not what you want in stock racing. I have teammates that charge at MUCH higher rates than that. It sounds to me like the problem may be the tray. What tray are you using? If it's one without an auto cutoff and you're just undoing each cell as the lights go out, you're not really equalizing the cells. It's a colse estimate. Someone mentioned that you may have a dead cell. That's very possible. Do you have one cell that's going out much earlier than all the others. Some of the trays that don't have a cutoff on them and take the cells down to 0.0v have a tendancy to do that. Especially if you accadently leve them on too long. Also, is this happening on just one pack or all of your packs?
If you're looking for charging/discharging/storing proceedures, just click on the Fukuyama Racing link in my sig. and go to the TECHNICAL INFO section.
As far as a tray goes. I'd reccomend something with an auto cutoff @ .9v. I like the Rayspeed. You can get it from Steve @ www.speedtechrc.com.
Novak is also coming out with what looks to be a very nice digial tray as well. As long as they have an auto cut off instead of the watching the bulbs method. If you let one cell go too long you can kill that one cell and flatten the pack.
Hope this helps.