In message <570CCF7BBB512341BA0EBA19E95084FB61D8@server.MicroBrix.local>
          "David Van Horn" <dvanhorn@microbrix.com> wrote:

> Typical fast charge is around 1C, with a range of 0.5C to 2C. Outside
> this range, the end of charge signals will become less distinct.

1C it is then. Guess I need to find a 2A PSU.
Am I right in thinking that trickle charging is actually bad for NiMHs?

> Check the cell specs carefully. 
> If they are cheap Chinese cells, I'd advise against anything faster than
> 0.5C. And I'd suggest a face shield and gloves.

Japanese actually. Kodak 1600mAh, "Made in Japan for Eastman Kodak Company".
Very nice cells actually - certainly better than the Chinese-made Uniross
junk I used to use in the digicam.

> 1: Final backup, a timer that simply counts to say 120% normal charge
> time.
> 2: A pipo over temperature cutout made into the battery pack.
> 3: Absolute temperature of > 40C
> 4: Rate of rise of temperature > 1C/min
> 5: Absolute voltage > 1.6V/Cell
> 7: Negative delta V of a few mV/Sec

Is it worth monitoring the current going into the cell, or is that not a
reliable way to detect end of charge?

> Good resources, though somewhat conflicting:
> 
> McGraw-Hill's handbook of batteries
> Sanyo and Panasonic data sheets.
> Data sheets from your cell manufacturer.
> Data sheets on charge ICs from Galaxy power.
> Data sheets from the Cadex web site.

Ooo! More light reading for bedtime :)

Thanks.
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