22 Dec
2022
22 Dec
'22
7:42 p.m.
On Dec 22, 2022, at 11:49 AM, Chuck Guzis via cctalk
<cctalk(a)classiccmp.org> wrote:
I can't speak with any authority on the NiMH vs. NiCd substitution,
except that I've replaced them on low-draw devices and used the same
charger. After 20 years of doing this, I can't claim to have destroyed
any NiMH, though I can certainly appreciate the self-limiting of
overcharge on NiCd cells.
I just read the battery chapter of the ARRL Amateur Radio Handboo, which discusses this
particular point at some length.
Among many other points it says (a) you can trickle charge a NiCd but not a NiMH, and (b)
NiMH requires a more complex charging algorithm than NiCd, so that NiMH chargers are also
capable of charging NiCd batteries safely, but NiCd chargers cannot charge NiMH cells
without the risk of damage.
I suspect NiMH charger circuits can be found. Buying $3 Chinese ones may work, or not; I
keep remembering that China disallows selling unsafe equipment within the country but
doesn't have any rules against exporting such things.
paul