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Old 06-13-2003, 08:21 AM   #1
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Default Newer Gp 3300's Losing runtime fast?


I have 2 packs of the newer Gp3300's and the voltage is 1.17+ and the run time on the label says 407 secs.My dilema is I have had these for about 2 months and when cycled on my turbo 35 the charge going into them is 3350mah but the discharge is coming out at 2850mah.Is this normal?I am wondering because I know that heat is part of the bleedoff of energy from the batteries,but a 500mah difference?Just wondering if this sounds about right.By the way,what are your cells taking in for a charge?Does 3350mah sound right?I hre of people with 3300's taking in 3500-3800mah.If this is the case,either I am treating these cells wrong or I got suck packs.Thanks guys!
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Old 06-13-2003, 08:59 AM   #2
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every one will tell you to store the gp3300s with charge... i did that with some kc-racing cells and lost some run time about 300mah , my newer cells , i discharge at 30 amps and tray until bulbs go out... i still have yet to lose runtime, charge going in at 3700-3800s and internal resistance is the same or just barely higher. So much for partial charge.
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Old 06-13-2003, 10:31 AM   #3
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The turbo 35 can monitor each cell, right? It could be that one poor cell is pulling the pack down. Or it could be incorrect charge/discharge settings. Or the whole pack has had a problem, perhaps from misuse.

I've had a couple of problems with my GP3300's - slightly mistreating them (charging before they are fully cool, at a 6A rate. 0.03v cutoff per pack) has caused them to get VERY hot during the charge. I've noticed a drop off in runtime of around 10% on about 4-5 cells out of 3 packs. Very annoying - and essentially my fault. My Sanyo 3000's were more forgiving of slight mistreatment.

So my advice - LET THE CELLS COOL TOTALLY BEFORE CHARGING - I know this is always said, but make sure - one oversight could cost you.

As for part charging - I don't really see the point - you buy the cells discharged, and they shed up to 10% of their charge per day, so a part-charged NiMH will be vitually flat within a week anyway. So long as the cells aren't stored trayed to 0v, I don't believe there will be a problem.
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