Charging NIMH Batteries at 200 mAh?

[MINIRCPLANES]

Folks,

I'm confused about what should be the proper charge rate for NIMH batteries. I have a Promax Activator PEAK charger and they claim that a 200 mAh "trickle" charge rate is safe for these batteries. A buddy of mine has the Great Planes Electrifly PEAK charger and the instructions also claim that 200 mAh is safe.

I've been charging my batteries at 50 mAh using my transmitter charger as suggested by Tom Hunt's in his RCmicroFLIGHT July 2000 article "Caring for NiMH Cells". I would like to use the field charger instead to get more flights.

If charged at 200 mAh will the batteries be damaged? Is the total number of cycles reduced? Would the same hold true for 220 mAh, 300 mAh and 720 mAh NIMH batteries?

Thank you for your help,
Felix Lopez
minircplanes@aol.com

[Wings]

What capacity is your pack? That determines optimum charge rates.

In general, the recommended charge rates for NiMH cells are C/10 (1/10th capacity) for slow charging and no more than 1.5C (1.5 x capacity) for fast charging. I personally try to avoid exceeding 1C rates as much as possible.

You should slow charge your packs for the first few charges to allow them time to develop to their maximum potential, and periodically slow charge the pack to equalize the cells. In general, the more often you can slow charge, the better. Slow charging is easier on your battery packs, yes.

Fast charging packs shouldn't hurt the cells significantly unless you use too high of a charge rate (NiMH are somewhat sensitive to heat and will suffer damage) or are careless with them.

Use a charger with delta peak detection built in (NiMH compatibles) and take care of your packs, and they will serve you well. :)

Wings

[2NG]

Field Charger/ using conventional methods (http://www.radiocontrolzone.com/forums/showthread.php?s=&threadid=77932) check out the way I converted a chager to charge in the Field