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cutty01
07-11-2008, 02:28 AM
Would any of the charging experts out there mind giving me some guidance when charging a NiMH 7cell 2600mah battery using the BC6-10 or similar? I just bought the BC6-10 and used the videos for charging LiPos but need some help in what to do (or not to do) when charging NiMH. I also purchased the temp probe and plan on using that too. Finless offered to do a video on NiMH in the future but until then some written advice or setup tips would be greatly appreciated. Thank you in advance...

RC Accessory
07-11-2008, 06:56 AM
Would any of the charging experts out there mind giving me some guidance when charging a NiMH 7cell 2600mah battery using the BC6-10 or similar? I just bought the BC6-10 and used the videos for charging LiPos but need some help in what to do (or not to do) when charging NiMH. I also purchased the temp probe and plan on using that too. Finless offered to do a video on NiMH in the future but until then some written advice or setup tips would be greatly appreciated. Thank you in advance...

With Ni-xx charging, there are 2 modes: Manual and Automatic.

This is the default mode when you select either Nimh or Nicad programming. The charger will detect the the # of cells based on the voltage of the pack so you do not set the cells or voltage.

In manual mode, you set the charge rate and that is it.

In Auto mode, you set the Current Limit. The Current Limit is the setting that will tell the charger the max charge rate to charge the pack at. Auto mode will allow the charger to test the battery and set the charge rate based on the condition of the battery, wiring ect.. Since the BC6-10 can charge up to 10 Amps, you have to set the Current Limit to the max amerpage you want the charger to charge at.

To get into Auto mode or back to manual mode:

When the charge rate or Current Limit rate is flashing, press both the INC and DEC buttons at the same time.

cutty01
07-11-2008, 10:21 PM
Since the BC6-10 can charge up to 10 Amps, you have to set the Current Limit to the max amerpage you want the charger to charge at.


Thanks Evan, it seems that Auto mode is the best hands off option for me. Is it safe to charge a NiMH at the full 10A? When doing research I saw in the Triton JR manual it says to charge at 1.3A for a 2 hour charge or 2.6A for a 1 hour charge. But I also read elsewhere that is actually beneficial to "overcharge" NiMH at a very high Amp, is there reasoning to that? I dont want to ruin my battery or worse yet, start a fire.

Also if using the temp probe, will the charger shut itself off when the temperature of the battery gets too high?

Wyn
07-11-2008, 11:01 PM
General rule for fast charge amps with NiMh or NiCd is 1C, but never above 2C or below 0.5C. "C" is the MAH of the pack. If the pack is a higher impedance type, it will heat up more, so tend towards less than 1C.

So, for a 2600 7 cell pack, 2.6 amps is 1C. The battery should get warm at the end of a full charge, but not hot. The temp probe can cut off the charge on high temp (the temp cut-off is adjustable), but I've never used it myself.

Some "over-charging" happens regardless of the charge amps. When the cells are full, it creates extra heat that lowers the cell impedance, which lowers the voltage, which tells the charger when to stop. The best charge is one with minimal temp increase at the end.

BTW- the NiMh and NiCd delta peak trigger voltage is a setting that determines when the charge terminates due to lowering voltage as the charge completes. If it's too low it can terminate prematurely; too high and there can be too much heat generated in the battery.

RC Accessory
07-11-2008, 11:04 PM
Wyn is 100% correct. Auto mode or manual, it does not matter. In Auto mode, you would set the current limit to 1C. In manual mode, you set the charge rate to 1C.

cutty01
07-11-2008, 11:27 PM
Thank you both for sharing your detailed knowledge. Hopefully this will be useful to others as it was for me. Cheers.