I should have payed closer attention in Radio/Electricity class in school, because now I need help.
I recently bought a Accu-Cycle Pro Series Elite charger from Tower Hobbies and I'm having difficulty undestanding Volts/Amps/mAh and charging rates for a variety of flight packs.
Can anyone suggest a chart or formula for 'safe charging', 'quick charging' and 'cycling' battery packs?
I have back-up batteries for my transmitter and receiver, but I would like to charge one set of batteries while flying with the others. This would be a field 'quick charge'. ____________________________________________ Earl Scherzinger AMA #40329
Well, read a ton, and visit Red's website. Reds RC Battery Clinic (or similar - sorry red.) The "formula" for charging batteries is easily kept in your head. Keep thinking in terms of "C." I'll try to explain below. "C" changes for each size and type of battery, but is easy to remember.
The volts question is easy - for that charger, just set the number of cells. It does the voltage part for you. Amps - the flow of energy. mAh - "milli (1/1000) Amp Hours." how much energy is stored (how large is the fuel tank.) 1000mAh is the same as a 1Ah battery. Charge rate - Often described in terms of "C." "C" depends on the capacity (mAh) of the battery. Charging a 1000mAh battery at 1C means to charge it at 1000mAmps (1 amp.) All things being equal, charging a battery at 1C will take one hour. (Although it could take longer depending on losses, type of charging algorithm, etc.)
Fast charge: Depends on your battery; check the specs. I think most NiMh can be charged at 1C. So your 700mAh NiMh battery will likely take a charge at .7 Amps, and should take one hour. Your transmitter batteries may like to be charged slower - say C/3? So your 600mAh NiCd may like to be charged at .2 amps for 3 hours. Slower charges (lower charge rates) are always safer. Some may say that high charge rates will give more power for high output applications (discharging in minutes, rather than hours like your transmitter.) Heat is the enemy - both in discharging and charging. Too hot, and cells can be damaged.
I'm learning too, so corrections are welcome.
C
Earl Scherz> I should have payed closer attention in Radio/Electricity class in school,
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