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Self-discharging pack?

I have a new, no-brand 6-cell 1700 SC pack that I first charged at 100ma, then subsequently charged on "auto" mode with my Simprop Intelli-control charger (same as FMA Nova). (The pack came with a Chinese R/C tank I bought while perusing the Raindentech site for CMP ARFs.) It has been charged about four times.

It seemed like the pack was running down quickly between charges. I checked the tank with my multimeter... nothing at all flowing with the switch set to "OFF." So I charged the pack last night, left it sitting out all day, then put it back on the charger tonight. It took 865mah worth of charging. 1/2 discharged in one day? Hardly seems possible.... :-(

I guess I'll chuck it and buy a Sanyo pack! Should I disassemble it and save the good cells?

Good flying, desmobob

Reply to
Robert Scott
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Don't trash it yet. If you are making judgment on the pack based on how long it takes to charge it is leading you astray. Any pack will take a fair amount of charge after being fully charged before the charge will terminate. Depends on the charge rate and the pack characteristics. To tell if you have a problem, charge the pack, then discharge with a charger that will read out the discharge capacity. Charge it again and let it rest for 48 hours, then discharge the same as before. If you have lost a significant amount of capacity (more than 10%) then the pack may be headed south.

Reply to
Red Scholefield

Hi Red,

I've never kept track of how long it takes to charge it.

But more than half the capacity of the pack? It's a 1700 mah pack and it took an additional 865mah after sitting for about ten hours on the bench, not connected to anything.

I'll do that and see what figures I get. Thanks for your response.

Good flying, desmobob

Reply to
Robert Scott

I had a couple of NiMh packs that had been sitting around so long that they measured nothing. I left them on a wall-wart charger for a day or two until they started to show a charge, then I put them on my Swallow charger and gave them about 4-5 charge-discharge cycles (500mA charge, 300mA discharge). The first few cycles they took and gave out about 300-500mAH, by the last cycle they were giving their rated 1500mAH. So it's quite possible that with a bit of cycling your pack might come up to scratch.

Reply to
Poxy

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