How to charge my Battery ? to read the number [752] Published:2016-01-09 15:18:57
Is it better to charge fast or slow?
Sees like you never have a choice, so for practical purposes this rarely matters.
Most chargers don't let you set the charge speed.
But let's say you have a fancy charger that does let you set the charge rate.
In general, slower is better. Slower preserves the cycle life of the battery.
I suggests that the optimal charge rate is 200mA, and that's what the default is for its BC series.
That means a fully depleted 2000mAh AAA would take about ten hours to charge.
But of course there's a catch to charging that slowly, As there's always a damn catch:
If the battery charges too slowly, the charger might miss the voltage change and not stop charging.
If it keeps charging then it reduces the cycle life. Personally I don't think this is anything to worry about, because the chargers that charge very slowly generally employ backup methods to make sure they don't charge too much. For example, the La Crosse BC-700 primarily uses negative delta voltage detection (-dV/dt), but it also uses high voltage, max temperature, max energy input, and a safety timer as backups. However, to be safe, NLee the Engineer suggests bumping up the charge current for AA's to 500 or 700mA. (Slower than that is fine for AAA's.) I do that myself because 500mA gives me a lot faster charge, and it's a good compromise between the BC-1000's default of 200mA and the blistering 1800mA charge.
So in general, 4-5 hours is probably a good charge time.
Faster than that potentially reduces cycle life, and too much slower than that could possibly cause the charger to miss the cutoff, making the charger keep charging, and reducing cycle life. A 4-5-hour charge means about a 500 mAh charge for most AA's, and 200 mAh for most AAA's.