Are your old Eneloops still going strong? - a survey.

[illumiGeek]

...The Eneloops that have an 06 date code seem to be doing the best...

They have a date code? I guess it's like the horse said, you learn something new every day.

I have a bunch of older style Eneloops, and I tried testing them once to see if I could sort the older ones from the newer ones, but they all tested within a few percent of each other, in spite of some being almost new, and others several years old. After reading about a date code in the post above, I took a look at my white Eneloops, but still did not find anything? So I went to the great oracle of wisdom (google) and found the codes. Dayum it's hard to see (then again, I'm quite far sighted).

Anyway, to make a short story long...

With the help of my trusty Fenix L1T V2 R2 (and some strong reading glasses), so far I have found:

8 from 2006 (06 07TA)
8 from 2007 (07 08TL) ** The 07s are really hard to read!
8 from 2008 (08 08ER)

So that's 24, from 3 successive years. Probably have more somewhere (I have way too much battery powered crap, lol!). I just popped 4 of the the 2006 cells into my BC900 for testing. We'll see if they still test like new. Many of these have been cycled hundreds of times, and most have been in high drain hotwire mods and diving lights (often sucked dry). They've usually been charged on my LaCrosse BC900 or Maha MH-C9000 & MH-C801D. A few have been run through an Eveready 15 minute battery cooker, but not very often.

The only Eneloops I have that I know have lost some capacity were the "Duraloops" that were in my LaCrosse BC9009 when it went into melt-down mode. But even though they got too hot to touch, they still work to this day, and last I tested them they had around 1650-1700mA capacity. Three of those are in my PS3 Sixaxis controller (which I use with my PSPgo now), and I don't recall where the 4th one went (probably in a clock).

I wonder how old the rest of my Duraloops are? I've got quite a few of those as well. And I've also got a bunch of the newer 1500 cycle 'loops.

Anyway... I'll test my 2006 cells and report back.

EDIT: First test pass complete!

LaCrosse BC900 (v35): Charge/Test mode (1000mAh charge, 500mAh discharge)
Eneloop AA cells from 2006 (06 07TA)

1=2060
2=2050
3=2040
4=2030
5=2020
6=2000
7=1651 *
8=1590 *

Not bad results! Six out of eight 5.5 year old batteries still testing at or above their new factory specifications. The last 2 cells tested below spec so I am running a break in cycle on my C9000 and then I'll re-test. UPDATE: re-sorted by capacity, and break in still running on low cells (really slow process).

 

[illumiGeek]

Okay, final verdict. Several attempts to resurrect those weak cells failed. Ran refresh cycles on both the Maha C9000 and LaCrosse BC900, and also tried a break in cycle on the C9000. Final test pass on the BC900 showed their capacity at 1702 & 1572. So it appears that 2 out of 8 of my 5.5+ year old Eneloops are showing their age. However, 6 still test over 2000mAh capacity, which is within the specifications for new cells (1900 minimum, 2000 typical).

 

[shelm]

BC900 showed their capacity at 1702 & 1572

So what does this mean in practice, what's the advice here?

( should we dispose the two cells?, or would it be waste to do so? )

 

[SilverFox]

Hello Shelm,

I generally retire cells when they fall below 80% of their initial value.

Eneloop cells start off at around 1900 mAh. 80% of that is 1520 mAh.

Tom

 

[shelm]

Good rule of thumb, thanks!
If we take normal care of our Eneloops (e.g. topping off the unused cells on the 1st of every month, i.e. 12x per year; and a break-in with these unused cells 1x per year), they should not be aging until years later, am i right?

That's the whole purpose of buying Eneloops (=top quality cells)

 

[n3eg]

a couple of AAAs that eventually got killed, presumably by unfriendly charging in a cordless phone handset, which I don't think counts as an Eneloop issue since it has happened with other cells as well.

Interesting - my only bad Eneloop cell was in a homemade pack for a cordless phone. My big Eneloop torture test is a set of Duraloops in a two-way radio battery that is used 5 days a week since last February and charged at 0.5C every night - so far, no loss in runtime.

 

[illumiGeek]

So what does this mean in practice, what's the advice here?

( should we dispose the two cells?, or would it be waste to do so? )

I hang on to cells that still have usable capacity. Those 2 will probably go into things that don't need much current (clock, mouse, keyboard, etc.).

Good rule of thumb, thanks!
If we take normal care of our Eneloops (e.g. topping off the unused cells on the 1st of every month, i.e. 12x per year; and a break-in with these unused cells 1x per year), they should not be aging until years later, am i right?

That's the whole purpose of buying Eneloops (=top quality cells)

Why bother "topping off" LSD cells? The "whole purpose of buying Eneloops" is that they don't need to be topped off.

 

[Trancersteve]

I hang on to cells that still have usable capacity. Those 2 will probably go into things that don't need much current (clock, mouse, keyboard, etc.).


Why bother "topping off" LSD cells? The "whole purpose of buying Eneloops" is that they don't need to be topped off.

Because they aren't zero self discharge cells?

Personally, I top up my 'standby stash' after between 3-6 months depending on the brand of LSD cells.

 

[Wrend]

I don't bother topping of my Eneloop cells once they're off the charger. They self discharge so slowly that it isn't worth the effort for an insignificant amount of longer run time, and perhaps even more importantly, I match all my cells and only use them in series cell sets that get charged and used at the same time in the same devices together, so they remain equally charged as each other and wear evenly.

The self discharge rate of Eneloops decelerates over time, so they lose a higher percentage of capacity initially. So the difference in charged capacity from 0 to 3 months is going to be greater than from 3 to 6 months, and from 0 to 1 year than 1 to 2 years.

The main reason to top off cells (on an independent port charger) would be if you don't know how fully charged they are compared to each other. This would probably add less wear on the cells than using ones together that don't have the same amount of charged capacity.

To keep your cells in top performance (again, not really an issue for me) a slow discharge followed by a full charge would probably be even better, though it may add some wear to the cells.

 

[illumiGeek]

Because they aren't zero self discharge cells?

No, but their discharge rate is so slow that topping off frequently makes no sense. You gain what, an extra 100mA? Unless you have reserve Eneloops that are never being used -- in which case I'd suggest you rotate your cells -- or at most, top off once a year (anything more frequent than that is just a waste of time and energy, and probably causes pointless wear on the cells).

I rotate cells. When I pop spent cells onto a charger, I take some out of my charged reserve to replace them. As cells come fresh off the charger I put them into the reserve case upside down from the others, so that I can tell which need to get used next. Once the whole case is flipped I turn them all over and repeat. I also always pull from right to left which helps to keep things pretty even.

The 2 cells I have that are weak were in my Bluetooth mouse, which is charged on a cradle that has a series "dumb" charger. I didn't rotate those since the mouse had its own charger, but in retrospect, maybe I should have? Then again, they did last over 5 years, even with the abuse.

I don't bother topping of my Eneloop cells once they're off the charger. They self discharge so slowly that it isn't worth the effort for an insignificant amount of longer run time

Agreed!

...and perhaps even more importantly, I match all my cells and only use them in series cell sets that get charged and used at the same time in the same devices together, so they remain equally charged as each other and wear evenly.

I don't even bother with that. Look at my test figures above. Not counting the 2 cells from the mouse (which weren't in rotation) the difference is only 3% from the best to the worst. That's probably close enough to be considered margin of error. It's certainly close enough that I don't worry about balancing. When I tested all 24 of my Classic (Retro?) Eneloops a couple of years ago the difference was less than 100mA (<5%).

The main reason to top off cells (on an independent port charger) would be if you don't know how fully charged they are compared to each other. This would probably add less wear on the cells than using ones together that don't have the same amount of charged capacity.

I do that before filling my two 8 cell HID dive lights, but that's because I usually don't have 16 cells in my charged reserve and have to pull cells from other devices.

Currently I have 11 'loops in my charged reserve, and 47 in use in various devices. That's a total of 58 Eneloops. 24 "Classic" + 8 "Duraloop" + 26 "1500" types (and that's just the AA size).

Is that a lot?

 

[CandleLite]

I have 20 or so AA Eneloops that I have been using for a while, so I thought it was time to consider if I should replace them. A closer look revealed that they were all 1st Gen with dates around 06-0715 and 08-0600. So this means that these batteries are 9 to 11 years old and have been in continuous use for the past decade. They are spread out throughout the house in many applications like flashlights, remotes, mice and even a milk frother. I would not consider anything was of heavy use other than my Magic Mouse which burns through batteries.
I recharge them as necessary in my La Crosse BC-900 and apart from the occasional refresh they still take a 1900 or 2000 Mah charge. Some go to 2100 Mah. I have never had to discard a single Eneloop yet and it seems like there are still many cycles left in them.

Is this typical or am I just lucky?

I just ordered another 8 of the 4th Gen batteries because the electronic devices and flashlights have multiplied around here. I hope they give me a similar performance and longevity.

 

[bigfoot]

Is this typical or am I just lucky?

LOL, had to chime in -- pretty much mirror your experiences here, right on down to the milk frother and La Crosse charger!

Earliest cells on this end are from Aug. 2006, and they are all still going strong. (Although I use newer Eneloops in higher drain devices like GPS, radios, etc.)

Just imagine what not buying alkaline batteries for over a decade has saved! :thumbsup:

 

[martinaee]

Not sure if i have older than 2010 Eneloops, but I do have a bunch labeled "2010" in sharpie that are still great so they do last a long time.

 

[SilverFox]

Hello CandleLite,

I just recently retired some of my first generation Eneloop cells. They were used in a camera that didn't get much use. I think the lack of constant use just did them in. I have a few more in flashlights and they are still going strong.

Tom

 

[terjee]

I just recently retired some of my first generation Eneloop cells. They were used in a camera that didn't get much use. I think the lack of constant use just did them in.

I'm curious...

What made you decide it was time for them to go?

And did you try putting them through a refresh cycle?

Hope you don't mind me asking.

 

[Hugh Johnson]

I have some IKEA Ladda 2450, which I heard are arguably rebadged eneloop pros. One of them doesn't hold much capacity after a few cycles. This makes me want to invest in some regular eneloops.

 

[SilverFox]

Hello Terjee,

On a Break In cycle they came in at 900 mAh of capacity. In addition they seem to have lost their low self discharge capability. I would put the cells in the camera and on about the second use within a couple of weeks the voltage would drop low enough to shut off the camera.

Tom

 

[WDG]

My oldest Eneloop AAs are from around July 2007, and my newest are from around November 2008. All 2007 cells are high-resistance, and about half the 2008s are, also. There seemed to be a difference between the two sets in how long that took to happen, with the 2008s lasting longer. My normal-resistance 2008s range from around 900mAh to around 1500mAh remaining capacity. Not bad, IMHO.

I continue to use high-resistance cells in low-draw devices until the old C.Crane charger turns up its nose at them.

 

[filibuster]

...I continue to use high-resistance cells in low-draw devices until the old C.Crane charger turns up its nose at them.

I might be time to retire your old C.Crane charger. If it's the old quick charger like the one I have it was made for old NiCd and NiMh cells that needed a trickle charge to keep them topped off until you pulled them out of the charger. The eneloop and newer LSD type NiMh cells don't need a trickle charge and as I understand it, a trickle charge can degrade their performance over time. I wonder if that's why you are seeing the high IR on your eneloop cells?

 

[filibuster]

I just did a test on a pack of 10 year old 1st generation eneloop cells I had in storage. They were dated July 2007 on the cells.

Straight out of the package I did a discharge test and they showed a capacity of just over 1100mAh @ a 400mA discharge, which means they held onto over 60% of their original 1900mAh capacity after 10 years of sitting on my basement shelf.

After a few charge discharge cycles they tested to just over 1800mAh during a 400mA discharge meaning they've only lost about 5% of their original capacity after 10 years of storage.

From the looks of things, it appears if you use them or store them you can expect to get 10 years and beyond of good life out of these eneloop cells!