battery charger question

[cavingjan]

What is the difference in charging of NiCD and NiMH batteries? I know most of the newer chargers will do both. I found an old Panasonic Slim Charger that is a nice small charging unit that is for AA & AAA NiCD batteries and wondering if I could occasionally run some NiMH batteries through them. The output is 2.4V 90mAX2 / 35mAX2. (Obviously it charges in pairs and I'm assuming the 90 is for AA and 35 is for AAA).
Any EEs out there who could help me out?

 

[RU482]

Well, as far as the batteries are concerned, you have to fully discharge NiCd batteries before charging. NiMH can accept a charge at any point.

 

[gopunk]

no, it has to say it can do both. otherwise you'll screw your batteries up, since it's a different chemistry

 

[Lunarcycles]

cavingjan

You posted this over 10 years ago. Do you remember how the SlimCharger works? Do the LED indicators stay red and then turn another color (green?) when the batteries are fully charged? It would be a trip back in time to get an answer from you. I'm trying to charge my batteries as I write this, though.

Thanks,

 

[Kalvin00]

Dude hasn't been active since 2008. Don't think he is coming back...

 

[Red Squirrel]

lol

 

[phucheneh]

...should I answer him, anyway?

Some chargers always stay red to say that they're charging; other switch colors when 'done.' Unless you can find some documentation on your older-than-dirt charger, all you can do is make assumptions. If the LED is just a little red dot, and has a red appearance even when not powered, I highly doubt it's going to change colors.

And yeah, you can charge NiMH and NiCd with the same charger...or try to. It just might not work with NiMH, as they need to have the voltage varied as the temperature goes up. IIRC NiCD's can charge off a constant voltage.