So, if I'm using NiMH batteries and a standard charger (ie either does 2 or 4) what if I have 2 batteries, one nearly fully charged and the other nearly dead, and charge them together? Will the charger cut off when the first is fully charged leaving the second still virtually empty?
I think this is happening and could be the reason why apparently fully charged batteries show as only 50% charge in my Garmin and other devices. If so, I guess the solution is either to use and charge them in pairs (tricky to manage) or get a single battery charger?
Or am I talking rubbish again?
cheers
A decent battery charger should treat each battery as a seperate circuit, sounds like either yours doesn't or one of the batteries is knackered.
It'll try to charge them both but when the nearly full one becomes full it probably thinks both are full and stop. If it swaps to a trickle charge mode them you might be able to slowly charge both.
as long as you leave them charging long enough, the lower charged cell should eventually catch up. If the charger pays any attention to the voltage it'll see the sum of the 2 cells in series and keep going till it gets in excess of 2.4V
The worst case is to run down 2 differently charged cells in series in the target equipment, as when the lesser charged cell runs out it gets driven backwards by the current resulting in a permanent loss of electrolyte
dave_rudabar +1http://www.batterylogic.co.uk/technoline/technoline-BL700.asp
Anyone that uses rechargeable AAAs or AAs should have one of these. Brilliant little devices.
thanks, thought the duracell charger I bought was up to the job, but now I've seen the charger in that link.......!!
cheers
but now I've seen the charger in that link.......!!
I have one too - great piece of kit. It can charge, discharge and even measure the total capacity of each cell seperately