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simple nimh charger

J

John Doe

The only experiences I've had with NiMHs has been bad.

For one, there's no such thing as a "simple" NiMH charger.

Says who?
For another, NiMHs have a shelf life of days when they're new,
and when they get to be about a year or so old, they don't even
hold a charge at all, even with a "smart" charger.

That would be news to all of the major AA/AAA battery makers, and an
experienced contrary to millions of happy consumers.

Nickel metal hydride (NiMH) far exceed the capacity/usefulness of
nickel cadmium (NiCad). Recent AA capacities exceed 2500 milliamp
hours. That's over four times the capacity of NiCad AAs?

All of my NiMHs are still working great after several years of use.

They continue working for weeks after installation.

If you want very long shelf life, use alkalines.
That's always been the rule.



<Snipped rest of troll>
 
L

linnix

Rich said:
The only experiences I've had with NiMHs has been bad.

For one, there's no such thing as a "simple" NiMH charger.
For another, NiMHs have a shelf life of days when they're new,
and when they get to be about a year or so old, they don't even
hold a charge at all, even with a "smart" charger.

"Smart charger" can be good or bad.
I just tossed about $15.00 purchase price (I don't say "worth,"
because they're essentially worth squat) for two sets of four
NiMHs. I still have the charger, but have no idea why I'd want
to keep it - probably because it's touted as being able to do
NiCds as well. :)

What is the current of your charger and rated capacity of your NiMH?

A good charger must pump enough current into the cell to oxidate the
metal. A low current simply heat up the cell without charging it.
But my camera explicitly says "Do Not Use NiCds", (I initially
bought the NiMHs specifically for the camera - got a second set
when I found out how often I had to recharge the worthless things),
so I'll be getting some alkalines for it. A couple bucks every few
years is worth the cost, vs. the PITA that NiMHs turned out to be.

NiMH will self charge in weeks. You need a properly designed charger
to keep it charged. In our charger, we pump high currents into it in
pulses and measure the voltage and current in both states (connected
and disconnected).
 
M

Michael A. Terrell

linnix said:
NiMH will self charge in weeks. You need a properly designed charger
to keep it charged. In our charger, we pump high currents into it in
pulses and measure the voltage and current in both states (connected
and disconnected).


Self charge? Another perpetual motion device?


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida
 
E

ehsjr

linnix wrote:

What is the current of your charger and rated capacity of your NiMH?

A good charger must pump enough current into the cell to oxidate the
metal. A low current simply heat up the cell without charging it.

Bullshit. And you know it.

Ed
 
L

linnix

Michael said:
Self charge? Another perpetual motion device?

Sorry about my fast fingers. Should be 1. self-discharge and 2.
measure the voltage and temperature.
 
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