Recharging Alkaline Rechargables using NiMH charger?

HotDog-Cart · Post by **HotDog-Cart** » Mon Jan 12, 2009 8:59 pm

Hey guys. My dad bought some Pure Enegery Alkaline Rechargable Batterys. I dont have a charger for these. Will they charge in a rayovac NiMH Charger?

If not, whats another type of charger I could use? NiCD? (We cant find the right charger for these locally. So I want to try another charger.)

Post by **bicostp** » Mon Jan 12, 2009 9:24 pm

I'm pretty sure you need a special rechargeable alkaline charger to recharge rechargeable alkaline batteries. For one thing, they run at 1.5v instead of 1.2...

HotDog-Cart · Post by **HotDog-Cart** » Mon Jan 12, 2009 9:30 pm

So whats the worse that could happen if I tried to charge them with this Ni-MH charger?

Kurt_ · Post by **Kurt_** » Mon Jan 12, 2009 9:45 pm

You'd destroy them.

Why canâ€™t I use my NiCd/NiMH charger to charge Grandcell Rechargeable Alkaline batteries?

* The power supply needed to recharge a battery depends a great deal on the internal chemistry of the battery.
* Grandcell Rechargeable Alkaline batteries are composed of a different chemical system from NiCd and NiMH batteries, and hence require different power parameters when it comes to charging.
* A NiMH / NiCd charger applies constant current without any voltage regulation. A Rechargeable Alkaline would leak/vent in this type of charger, making the battery useless. The venting results from a pressure build-up caused by the electrolysis of the electrolyte in the Rechargeable Alkaline battery.

http://www.grandcell.com.au/index.php?o ... &Itemid=47

palmertech · Post by **palmertech** » Mon Jan 12, 2009 9:46 pm

I know what happens.

They just wont charge right, and because the charge moniter is made for ni-mh, it will either kill them, or just not charge them enough.

EDIT: Kurt beat me.

bacteria · Post by **bacteria** » Tue Jan 13, 2009 2:55 am

I recharged some alkaline batteries a few months ago in NiHM chargers - if you leave them for more than about an hour they leak a bit or fizz or pop slightly; ie battery killed. About 30-45 mins is right; was getting up to nearly 1.7v when they came out and worked fine; however noticed something interesting - after a while (weeks) the voltage dropped on the recharged cells - most of them anyway.

You don't get the equivalent of new cells by recharging alkaline cells, but can be useful if your cells are starting to drain a bit and you therefore have nothing to lose by trying to beef them up a bit - only going to be binned anyway...

palmertech · Post by **palmertech** » Tue Jan 13, 2009 2:59 am

I think you may misunderstand, Bacteria.

I don't know about the UK, but here we have actual rechargable AA cells, that are a slightly different chemistry and design, with special chargers. He says the ones he bought are rechargeable AA alkalines, so you do have something to lose, as apposed to normal alkaline cells, as they can be used oer and over, like ni-mh.

bacteria · Post by **bacteria** » Tue Jan 13, 2009 6:00 am

Oh, ok. Not seen rechargable alkalines in the UK. Didn't know they were about. Ok.

Kyo · Post by **Kyo** » Tue Jan 13, 2009 8:55 am

You should really buy a smart charger, bacteria. No wonder you keep complaining about Ni-MHs (with which I've made great experiences)