when recharge batteries (nimh)?

FILIPPO

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I'd like to know when do I have to recharge my batteries.

i have read somewhere that the best is when you see the light dim...but this is a very variable range.

do you know a voltage rate that is the perfect moment to charge batteries?

this may be a stupid thing but you know very well that I'm not good with batteries and I'm afraid of spoiling them:shakehead

thanks in advance
 

worldedit

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Jul 4, 2007
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For all i know, you dont have to discharge the batteries everytime. Its enough to do that every few weeks. Fully discharging them every time will lower the life span. The cells should be pretty empty at 1.1V. My charger stops the discharge at about 1V, but thats under load.
Its best to get a charger with -deltaV termination and discharge funktion.
 

WildChild

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I think the best with NiMH is NOT to charge often (top-off), because with every charge, the charger will overcharge slightly the cell before detecting it's full (-dV/dT). Every overcharge will reduce the lifespan of the battery. On the other side, you should not overdischarge under 0.9V under load. Usually, when lights start to dim, it's time to recharge and with most lights, cells are not overdischarged.
 

Mr Happy

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I think if you notice the light dimming at all, it is time to recharge them. NiMH have a fairly flat discharge curve, so once you can detect a drop in brightness the batteries are nearly empty.
 

FILIPPO

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ok so...

recharge batteries when the light is something yellow (or dim) and I'll never have overdischarging problems.

ook thanks!:wave:
 

Anders

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Hello FILIPPO.

It is good to charge your cells regularly with 0.1C/16 h to balance the cells when used in flashlights with more than one cell and as Mr Happy wrote directly charge the cells when you notice any dim light.


Anders
 

lctorana

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When I see a torch dim, even a little bit, I take out the cells and test them. Usually, ONE cell is low voltage - time for some attention.
 

cave dave

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It might depend on the light. For instance the fenix P2D circuit can seriously overdrain batteries so its best to charge early on that model.

It is very difficult for the human eye to detect the dimming of most lights.
 
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