Eneloop battery life?

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Just bought some standard AA 2000 mAh Panasonic Eneloops for my Xbox controller, since it eats the alkalines in less than a week. I got the Eneloop brand because of the proven low self-discharge and number of recharge cycles, but how long are they actually rated to last in years? I can't really find any good data on this; maybe there isn't any. Will they last decades potentially, if they haven't hit the maximum number of charge cycles at that point? I know alkaline chemistry is different, and most of them have a rated life, usually 5-10 years after manufacture date, then they expire. I'm assuming since NiMH batteries are rechargeable, their life is limited by charge cycles (and potentially use), rather than time.
 
I have used eneloop batteries for about 4 years in my camera flashes. (semi-pro; I've shot approx 60k photos in that time) life of the battery depends on the quality of the chemistry. so far good - but not very old yet.
 
I have dozens of eneloop AA batteries that I've used for years in metal detectors and trail cameras. Can't put a number on their life expectancy because they are all still going strong.
 
battery life is based on charge cycles, also epth of discharge and charger quality. Cheap chargers overcharge the cells and partially damage them. No battery manufacturer will tell you how to make their batteries last forever or they would be out of business. Just look for user guides on battery maintenance and you should be fine for a long time,
 
I use Eneloops (AA & AAA) for most of my applications. I don't recall any life in years (time), only in charge/discharge cycles.
I like chargers that show each battery capacity. When I find one that doesen't have the capacity as the rest by a set margin then cull it out or use it in another application where shorter run time is not much of a concern.
Some chargers can discharge then recharge and display the mAh capacity, others may show charge mAh but if the battery wasn't discharged then it would only read how much was put in to termination.
Candlepower forum has been my go-to regards to reviews of not only batteries, but flashlights, chargers etc.
 
I have some that are around a decade old. I don't use them all that often but they do work quite well.

AmazonBasics are rumored to be the same thing.
 
Yup, no time limit. It's mainly charge cycles.

Just use a good charger and don't over discharge - over discharge is actually more harmful than over charge.
 
Originally Posted by Klutch9
Just bought some standard AA 2000 mAh Panasonic Eneloops for my Xbox controller, since it eats the alkalines in less than a week. I got the Eneloop brand because of the proven low self-discharge and number of recharge cycles, but how long are they actually rated to last in years? I can't really find any good data on this; maybe there isn't any. Will they last decades potentially, if they haven't hit the maximum number of charge cycles at that point? I know alkaline chemistry is different, and most of them have a rated life, usually 5-10 years after manufacture date, then they expire. I'm assuming since NiMH batteries are rechargeable, their life is limited by charge cycles (and potentially use), rather than time.


Why don't you update us in a few years?
 
My oldest Eneloop will be 11 this year. They are great batteries. You'll know when it's done when it won't charge any more or only lasts a short period of time.

Rumor has it that many of the "off brand" batteries (the retailer named ones) made in Japan are Eneloops. Ikea ones are good and cheap and rumored to be Eneloops. IIRC a 4 pack of AA is under $7.
 
I'm seeing a drop off of up to 10% capacity as early as 100 charging cycles (about 20 cycles per year average). I only discharge to 1.1v/cell and normally charge at .1C up to .5 C max. These are in 4 to 5 cell packs and they are not monitored per cell. Still the only NiMh I will buy these days.
 
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About half of mine are a good 10 years old.

I *can* state with absolute certainty that if you charge AAA at the AA rate that the AAA's will die a very quick death.
 
We probably have about 80 of these in service. Most are 7-8 years old, but some are approaching 10 years, including in below normal room temps (40 degree garage). Just guessing, but of that many, we've probably only lost about 10-15% during that time, mainly in cordless phones were not the best at re-charging them.

When someone really runs one down to where the charger (ours is an Opus) can't detect it, we bridge it to an alkaline for 15 seconds, then the charger sees it and it charges right up. That's the mark of a good battery.

In a quality charger with a good charge algorithm, they are very good batts, IMO.
 
I. Ought a bunch for a while to use in slr flashes. Recently I had a big mess of all my stuff and decided I wanted to test them.

All of mine are around 10 years old.

There was one envelop that failed, most still return around 1750mAH under a 500mA load, with the lowest in the low 1600s, and the highest tight in that 1750mAh band.
 
I have dozens of NiMH batteries of various ages- from probably 10-12 years old to 1-2. I have a couple box sets of Eneloops I bought from Costco (came with 8x AA, 8x AAA, and C&D adapters) about 4-5 years ago. The Eneloops are one of the best that I own. They reach rated capacity and still charge to 90%+ of rated capacity after several years. The performance is very consistent and they hold their charge well for months.

I have had varying luck with NiMH, depending on brand. Some brands have declined 50% or more in storage capacity over just a couple years (Philips brand and others.) I use a battery analyzer for all my charges, I highly recommend one both for the safest charge (computer controlled to prevent overcharging) as well as being able to monitor battery capacity and performance over time. I own an Opus BT-C2000 (for NiCd / NiMH) and an Opus BT-C3100 (charges Li-Ion AND NiMH/NiCD cells of most every common size) and a Maha MH-C9000 The Maha is very highly rated, but I prefer the Opus chargers. The Maha will reject many cells (due to high resistance supposedly) if it's not in 100% perfect condition-- in other words it refuses to charge many cells which still have useful life in them. I pop them in the Opus charger and they charge fine and I still get good service from the cells that the Maha won't charge.

Tenergy is another battery brand I've had excellent success with (especially their low self discharge), right up there with the Eneloops. I have a dozen or so that are still charging to 1600+mah after 10 years. Even the Maha charger will still accept them, and that's a rare feat! http://www.all-battery.com/ni-mhbatteries.aspx
 
Originally Posted by 92saturnsl2
I own an Opus BT-C2000 (for NiCd / NiMH)

I have the C2400, which is essentially the same charger as C2000, just without the C/D adapters. Great NiMH charger, although lately I've been mostly using the MiBoxer C4-12.
 
I know this is an old thread, but I recently looked in my bag and found a set of Sony Cycle Energy batteries that I'm sure were the same manufacturing as the first generation Sanyo Eneloop. They all have year and production codes, so those were made in 2008. I'm not sure when I put them in the bag that I found them, but I put them on a Panasonic charger and they were fully charged in less than an hour.

Just remember the current Eneloops are really made by Fujitsu after Panasonic had to sell off that battery division to avoid antitrust issues. But Panasonic owns the trademark and buys from Fujitsu. I'm not sure who else buys from Fujitsu, but the standard 2000 mAh AAs are really good. Unfortunately Costco doesn't have those any more. The Panasonic label started appearing around 2014. I still have quite a few batteries with the "14" date code and all are still running fine. I also have some older Sanyo labeled batteries. A few have failed, but only here and there. When they've failed I didn't see any liquid leakage like I've seen with alkaline. They might leak a little bit of dry dust out of the positive terminal.

I can't really say I would know much about how long they last as I no longer use them in any application where I would care. I typically use them in wireless mouse applications, and flashlights where I'll just charge them after a short use and rotate them in and out. I might have a 10 I use in single cell devices, a couple of pair for 2-AA flashlights, maybe 5 sets of 4 I use in 4-AA devices, a few AAA singles, and several 4-AAA applications (like a flashlight and a video remote control). I rather prefer these to using alkaline where I'll try to get as much out of them as possible rather than charge the batteries proactively.
 
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