Charging alkaline AA/AAA?

901-Memphis

Enlightened
Joined
Dec 4, 2009
Messages
289
Anyone have information or thoughts on charging alkaline AA/AAA cells? Some research indicates its possible at low current. I tried putting some AAA batteries that were at 1.35v on my Nitecore charger that will do 375 mah and it pretty much shut off in less than 5 minutes at the hard cutoff voltage of 1.60v. I only found one thread when searching from 2003 which is why i'm bringing it up again.

It seems i need a very low current charger, so it's not worth the time or money.
http://www.candlepowerforums.com/vb...echarging-non-rechargeable-alkaline-batteries

More of a curiosity than anything, i know it's not the safest thing in the world, i have seen plenty of accidents with people i know accidentally putting alkaline in a store bought NIMH chargers that made them leak bad, but if you had the right charger...?
 

archimedes

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Nov 12, 2010
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I use alkaline cells for approximately zero percent of my battery usage, so I don't really get the "money saving" angle either ....
 

fmc1

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Mar 16, 2017
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Long Island NY
Rayovac made rechargeable alkaline batteries and chargers starting around the middle of 1994. They were called renewal and their claim was that they could be recharged up to 25 times. In practical use you were lucky if they lasted 10 cycles before they leaked. They were however fairly popular since the only other alternative at the time was NiCd's. So when people had a choice between NiCd's with the environmentally unfriendly chemical or rechargeable Alkilines with a picture of Michael Jordan on the box lots of people chose Michael. Remember Eneloops would not be available for another 10 years, they came out in late 2005 for AA's and a few months later for AAA's.


The Rayovac renewal charger that I had back in the day had a safety fetcher that prevented someone from trying to charge primary alkalines in the charger. I'll try and explain how it worked. The positive contact on top of a rechargeable alkaline battery had the whole top of the battery exposed not just the button like on a primary battery. The charger made contact on the positive side via the outer ring and not on the button. This area is normally insulated with the wrapper on a primary battery. It is not insulated on a rechargeable alkaline battery.


As far as I know rechargeable alkaline batteries are no longer being manufactured by anyone so anything out there is old stock which makes them even more likely to leak. Juice, pure energy and blue planet were the last hold outs. Now rechargeable alkaline batteries a basically an EBay only item.


I see absolutely zero advantages to rechargeable alkilines over NiMh. NIMh batteries have a higher capacity, they can handle a lot more cycles, they are way less likely to leak, they are more readily available, they can handle higher current. I could go on and on but I think I have made my point.
 
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xxo

Flashlight Enthusiast
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Apr 30, 2015
Messages
2,993
They made special chargers for ordinary alkalines back in the 80's - at best you got a few charges before they leaked. These did not restore anywhere near full capacity of a new cell and generally worked best if you didn't run the cells down all the way. Back then some of us (kids at the time) used to recharge Eveready super heavy duty type batteries on dumb chargers used for NiCad batteries.....it worked sort of, though as with alkalines you didn't get a full charge and you only got a few charges before the cells leaked or stopped taking a charge and if I remember correctly you had to be careful not to charge too long or the cells would overheat - definitely would not recommend any of this foolishness today! Get some Eneloops and enjoy.
 

WalkIntoTheLight

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Jun 18, 2014
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3,967
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Canada
I've recharged alkalines a few times, mostly just for interest to see what happens. You have to charge them slowly, around 200mA is okay. I use a dumb slow charger for this. I have also used a charger meant for "rechargeable alkalines", which works nicely and has the benefit of stopping the charge when it thinks the battery is full.

I found that I was able to recharge about 20% of the capacity, as long as I did it before the battery was drained too much (50% drained was okay). The batteries would seem okay, but would usually start to leak pretty bad within a few days.

I think there are some risks with recharging alkalines. I don't think it's as risky as dealing with lithium-ion batteries, which most of us do all the time. But, it's possible they could pop if too much pressure builds up in them during recharging. So, keep a watch on them during charging, and do it in a place that you don't mind if caustic goo explodes all over the area.

Don't do it to save money, since the leaks will quickly make that impossible.
 

ArazelEternal

Newly Enlightened
Joined
Jan 26, 2018
Messages
34
I avoid using alkaline anything if at all possible. Any battery I can replace with a lithium or NiMH rechargeable, I do. There is a reason alkalines are known as alkaleaks in some circles. Not about to have a leaky alkaline destroy an expensive light or gadget. I have a few sitting around that I would like to find a use for to use them up, but not burn them up just to get rid of them. Most of the ones I have came with lights or other things. Havent actually bought alkalines for quite a while now.

I had a set of the rechargeable alkalines back when they were popular, but never was really impressed with them. Never tried charging a primary cell before. Just didnt seem worth the risk.
 
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