When do you retire old AA/AAA batteries?

turnipfarmer

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Mar 10, 2011
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I've got some old eneloops, which are around 10 years old and their capacity is around 1700mh however when do you guys officially retire an old battery?
 

Kestrel

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Many years ago I had one Eneloop AAA (750mAh) w/ very heavy extended usage; conveyed it to SilverFox, he said its capacity was down to only 150 mAh and did not respond to conditioning.

I do have an unopened 4ct pkg dating to 2006; they were only introduced in November 2005.
On their 20yr anniversary I'll mail them to someone here for analysis, lol.

 

turnipfarmer

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Cool, cheers guys. My chargers are still charging them but they've lost capacity over the years. Is there any other metrics of the battery that indicate battery health? Eg impedance etc?
 

WC8KCY

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Assuming your cells are 2000 mAh eneloop and not 2500 mAh eneloop Pro, 1700 mAh is still 85% of rated capacity--perfectly healthy by most any metric.

I have Epson NiMH cells from 1999 that still test out at 80% of rated capacity. Your eneloops may still have years of useful life remaining.
 

jtr1962

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When a smart charger rejects them, I charge them in a dumb charger. I find most "bad" batteries actually still have close to their rated capacity, but only at very low currents on the order of a few mA. This means they can still be used in low-drain stuff like wall clocks or LCD thermometers or remotes.

If a battery gets internal shorts, can't be charged much past 0V, then it's time to recycle it but not before.
 

GaryF

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I've still got 10 of 12 of my original 2006 manufactured Eneloop AA, and 4 out of of 8 AAA.

2 of the AA failed, one had physical damage, the other developed rapid discharge. I killed 4 of the AAA in a 4 cell radio with parasitic drain that kept discharging them to zero for long periods of time.

My 2006 AA's are down to about 1350-1400mAh, still ok, Mostly they have been used in single or 2 cell devices, and charged before they got deeply discharged.

17 years is pretty amazing.
 

letschat7

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I have an Apple Eneloop that doesn't work right. I keep it in the recycle bin.
 

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cave dave

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I have a graphing calculator that uses 3xAAA. It's pretty low drain and new good Eneloops will last a year. If they get so bad that they only last 2 mo its time for them to go. I also use ones that won't charge in a smart charger in rarely used remotes, and they seem to last till I charge them at the spring and fall time changes.
I think things like calculators, remotes, wireless mice can be pretty rough on cells though because they can drain them down to nothing while still working OK.
 

ampdude

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AA and AAA rechargeable batteries typically don't leak, so I just use them until they give no power any more or the charger won't charge them like the original response to this thread mentioned. Until just recently I still had some Nicad's from the late 90's that still worked fine. NIMH batteries usually have a pretty short life span.. shorter than lithium ion batteries. I'm surprised you have some ten years old, none of mine have ever lasted over 4-5 years. I have some AW lithium ions that are over 12 years old and still going strong and still very consistent.
 

Wrend

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They're rated down to 80% remaining capacity. At this point they tend to degrade exponentially, but yes, if they still work for you, then they still work. I still have all my Eneloops from 10+ years of buying them and haven't bothered testing their capacity very accurately as they still all hold a charge and work. However, I have taken some series sets apart when a cell stops performing as well as the others, so I have a few individual cells from those. They still work in single cell applications for me. They all still charge fine for me. I use them in rotation and have extra sets charged and ready to use. This is how I store them and generally I do not top them off again before use. It may be that one of these years I'll have several fail on me, but no sign of that yet. Cheers.
 
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MidnightDistortions

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I tend to demote them but I do have a stash of batteries that doesn't seem to hold a charge but until I dug out this black case Rayovac PS1 (they seem to have different PS1 models) that charges NiMH batteries and didn't realize it still works. The batteries that I used with it still work in lights so I tried a few batteries I thought were dead or no good. It appears the charger works well!! But really slow.

I got a couple of LaCrosse BC 1000s that didn't seem to charge the batteries nor keep them topped off. Probably because the internal resistance of these batteries is so bad that the smart chargers no longer will charge them.

The batteries kept being flat and didn't want to charge but seems to me the Rayovac is actually rejuvenating them. I did leave the batteries sit for so long that they're in need of refreshing but it seems the best way to refresh them now is to first get them charged to see if I cant knock some life into then again.


I'm looking around on google for more of these Rayovac chargers as they're no longer around. The ones that seem available is the rechargeable alkaline ones.

I don't know if the 3 in 1 Rayovac chargers will do the same thing but really the biggest thing with these older cells is they need to get charged up which they're not doing in the smart chargers. Either they cut off due to the -dV or timers. I have a Duracell charger but it's a dumb 2 shared volt charger but it does trickle charge them at the end of the charging cycle. I cant tell if it works as the light doesnt stay on.
 

Monocrom

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If we're talking white label Eneloops, all of mine are still going strong. Oldest ones are 5 years old.
 

letschat7

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I retired an Apple Eneloop last Feb that I hadn't used since 2016 or 2017. It was manufactured well before that and was back when Apple offered a recharger and two battery set.
 
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