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Old 03-16-2008, 07:52 PM
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CarbonJoe
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As mentioned above, charging at 1C (3.6A for 3600mAh, etc.) is generally safe for NiMH packs. However, I disagree with the "discharge as low as you can" statement. Different vendors batteries generally have different likes and dislikes. Most of the new cells will die permaturely if you take them below 0.9v/cell. Since these are "sport packs" and probably are pre-assembled, you can't do what the on-road guys do and discharge each cell individually. Most people only discharge the individual cells down to 0.9 to 1.0V per cell (5.4 to 6V for a 6 cell stick). Since "sport packs" aren't generally comprised of matched cells, discharging them as a pack will result in individual cells being discharged to slightly different voltages.

Thus, even if the pack voltage is 6.0v, all of the cells probably won't be 1.0v each. Some more, some less. Then when you charge them up as a pack, some batteries will "peak" before others, creating the chance of overcharging one of more cells in the pack. Overcharging = heat = bad. I have had a pre-made "sport pack" pop a cell. It ain't pretty. If your charger has a temp sensor, use it.

With good quality matched race cells, most of the on-road guys charge around 6A.
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