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The Natural Philosopher
 
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Default Battery Charger Times For Ni-MH???

Fred wrote:

"BigWallop" wrote in message
...

NIckel Metal Hydride Batteries need a low, slow charge ...........


That means my 2 hr charger is no good then



Not necessarily.

Fast chargers for Nicad and NiMh exist, that look for a drop in cell
voltage signifying end of charge. The acceptable 'fast charge' rate for
NiMh with a GOOD delta-peak xcharger is one hour, and 20 minutes for
Nicad. Needless to say I have done a full Nicad charge in 12 minutes
many times, so these are conservative figures.

Charging NiMh faster than one hour tho leads to reduced capacity
eventually and poor lifetimes.

The voltage peak on NiMh is also much smaller than Nicad, which means
the chargers AND THE WIRING TO THE BATTERIES needs to be of good quality.







I have to say, these batteries are hopeless if you charge them and expect to
use them in 2 weeks time. They'll be flat.



Yes, that is NiMh to a T. I've bitten the bullet and gone straight from
trusty NiMh to Lithium Polymer. Buit then, my requirements ae more
specialised...you are still stuck with a one hour charge, but the charge
life is in months, not dauys, and teh energu density is far higher...