At 09:14 AM 5/11/2005, Daniel Chia wrote:
>I agree with the comment on the maxim nimh charger chip. The trickle
>current I just way too high! I have to keep a watchful eye for full
>charge then quickly kill the charger else my batteries get really hot!
>Anyone know a workaround for this?

Sanyo "C" type cells are rated to tolerate C/10 trickle.

Cheap chinese cells would be especially bad with this. They tend to 
have problems with electrolyte, catalyst, and seals.

Too much electrolyte leaves too little air space, raising the 
pressure to the venting point.
Once vented, the vents don't always re-seal.

Too little electrolyte reduces performance in gross amp-hours.

The catalyst helps the H2 and O2 recombine, but it's expensive.
Less catalyst, and you can end up with a pressurized can of rocket fuel.

Vents can be either non-functional (see above) or leaky, allowing the 
H2 to escape, leaving very reactive O2 in the cell, ready to react 
with anything it can find, and not usually in a good way.


In general, I would not advise the maxim charger chips.

Galaxy power's chips are much better, as long as your system meets 
their assumptions (simple, uncomplicated,  no large variations in 
discharge current while charging, or ideally no discharge while 
charging at all., etc.


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