Longest storage life batteries

Guys just a hypothetical as to what battery type in AA stays useful the longest on the shelf. Not for end of the world zombie fighting, can also be people or businesses in the 2nd or 3rd world stocking up when stocks and funds are available. I know alkalines rate up to 10 years storage, lithium ultimate 20 years. I had been led to believe for rechargables their cycles or shelf life will be killing them at 5-7 years...

However then saw Panasonic AA eneloop with up to 2100 cycles and 10 year storage life... is this accurate?

Does this mean if I don't use the Eneloop for the first 10 years if I then charge it, it works for decent amount more years/cycles , or is it basically un-rechargeable at 10 years?

Not totally sure of the stats but forget alkalines as even if they have decent storage life the higher than optimal chance of leakage both in storage and in devices rule them out. My strong suggestion for anyone using them is to not store them longer than 2 years prior to their expiration.
Eneloops may be said to store 10 years but now the cost of them is more prohibitive for buying them and using them in that fashion, lithium AAs are now be far cheaper and 20 years of storage has them as the best long term battery. My advice if to not depend on batteries in storage longer than 5-10 years to begin to have a method of replenishing/recharging batteries available in emergencies and having a mixture of eneloops and lithium primaries available. I've only had one long power outage it was almost 10 years ago and it lasted over 4 days and I didn't have any eneloops only regular energizer AA nimh batteries and recharged 30 of them in a car charger using no primary batteries up during that time.
Unless you can get alkalines cheap with the drop in prices of energizer lithium AAs to $7/4 pack (less in an 8 pack per battery) name brand alkalines aren't as attractive.

Personally I don't think it is wise to buy a lot of eneloops and not recharge them but once in 10 years. I recommend recharging them every few years myself, you don't have to recharge them too often. I wouldn't count of eneloops having initial decent capacity after 10 years in storage you may have to cycle them several times to restore their capacity after that long in storage the voltage may drop lower than optimal. There is no sense in buying and storing a lot of batteries that aren't going to be used at all in 10 years that are rechargeable IMO.

I suggest a combination of batteries myself, enough eneloops for normal usage, with extras perhaps for constant usage (so some can be recharging while others are power the devices, and some lithium AAs enough for perhaps a day of normal usage to give you time to procure more or set up for recharging at the end of a day. Alkalines are ok for some uses in lower power modes on devices but the main problem with them is if you aren't using them up every 2-3 years and replenishing them the chance of leakage increases rendering them wasted. Alkaline stocks need to be inspected at least every 4-6 months and stored in such a way to deal with possible leakage as I've had 2 year old alkalines leak on me both in the package and out of the package and also in devices that were never used even once to begin with causing messes to clean up.

I guess its more important to have the means to recharge the cells when needed than stocking them for such a long time.
Sure, you need a convenient number of cells anyway, but a solar panel will cut some part of your stock and can be used to recharge when needed, without external help.
Also, you may want to take into consideration old lead-acid batteries connected to a solar off-grid system to be ready when needed.

I agree with Eneloops for rechargeable, and Lithium Primaries for long shelf-life.

Just also adding that unless AA form-factor is an absolute requirement, combination of LiIon 18650 for rechargeable, and dual CR123A could be worth considering. There are good lights out there supporting both (you need specific support for it, not all 18660 lights can use 2xCR123A).

There's also LiFePo4 batteries. In some ways, they are to LiIon batteries what Eneloops are to NiMHs. Downside of LiFePo4 is that they run at a slightly lower voltage, so you'd need to do some research of lights cutoff voltage etc. They also have a somewhat lower energy density than "normal" LiIon, but are safer, and should allow for a significantly increased number of cycles.

You can also get LiFePo4 in AA-form factor.

Lead Acid was mentioned. An alternative there could be LiFePo4-based batteries in typical lead-acid form factor. They're
ore expensive (2-3x), but 1/3 the weight for the same amount of energy, and unlike lead acid you can cycle them fully without causing excessive damage or wear. For a "This is where I store the energy"-part of a larger system/setup, it could be interesting.

mickb said:

Guys just a hypothetical as to what battery type in AA stays useful the longest on the shelf. Not for end of the world zombie fighting, can also be people or businesses in the 2nd or 3rd world stocking up when stocks and funds are available. I know alkalines rate up to 10 years storage, lithium ultimate 20 years. I had been led to believe for rechargables their cycles or shelf life will be killing them at 5-7 years...

However then saw Panasonic AA eneloop with up to 2100 cycles and 10 year storage life... is this accurate?

Does this mean if I don't use the Eneloop for the first 10 years if I then charge it, it works for decent amount more years/cycles , or is it basically un-rechargeable at 10 years?

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I actually answered it in my eneloop FAQ. So basically it just means that if you charge the battery for to 100% you will be able to use the battery from that initial charge 10 years later. And there should be about 70% charge left after those 10 years. See more explanation in my FAQ.

Actually I found some eneloops in Japan last week, that are from 2008/04 so I want to do a test to see how much charge is still left in them.. The package is new, unopened.... so Im a little excited to know. ... just have to wait 10 more months

dragosios said:

I guess its more important to have the means to recharge the cells when needed than stocking them for such a long time.
Sure, you need a convenient number of cells anyway, but a solar panel will cut some part of your stock and can be used to recharge when needed, without external help.
Also, you may want to take into consideration old lead-acid batteries connected to a solar off-grid system to be ready when needed.

Click to expand...

Solar panels are good but often outages are because of bad weather and there is not much sunlight till it clears. I've found the best thing is 12v charging (car chargers) as you only need a few gallons of gas to recharge a car battery in a vehicle over and over which can charge dozens of eneloops and solar charging setups can be costly plus investing in adapters and deciding on 12v or 5v systems and usb adapters and so on.....

I lost this thread, apologies it had great replies. So I take it the lower capacity eneloops are lasting longer than the higher capacity ones and getting to the 10 year mark theoretically.

Similarly I was wondering if there are LSD versions of 18650 that outlast the others or can handle more cycles?

mickb said:

Similarly I was wondering if there are LSD versions of 18650 that outlast the others or can handle more cycles?

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LiFePo4 are a cut above when it comes to cycle count, but run at a slightly lower voltage, and have a slightly lower energy density. You need specific support for them in both chargers and users of the battery.

That being said, most NiMH pre-Eneloop were poop, but most 18650 LiIons are pretty good. There's no need for a revolution in LiIons, like there was with NiMH. If you charge the cells about 4 times a year (or more), and don't cycle them daily, most will give you years of service.

I just got done testing a dozen 18650s pulled from 10+ year old laptop batteries, and ALL the cells that hadn't dipped too low in voltage are fully functional, has good capacity, and retains there charge well. I'll test them again by draining them in 3 months, to double-check that they kept charge long term.

Thanks Terjee.

Well I have learnt about the differences between chinese and Japanese eneloops being fairly substantial. As such I was wondering if anyone can verify this as probably being the Japanese version? https://www.nkon.nl/rechargeable/aa-size/8aa-panasonic-eneloop-ocean-in-blister.html

As it appears to be chinese versions only in Australia and the above European company can ship Japanese to me, I was going to order through them.

I can't say for sure about those, but I do know NKON sells others that are made in Japan. I've usually been getting the four AAs in a non-blister pack, that mentions on the page that they are Japan-made.

Get eneloops and use them as the time.
With the money you save, buy Energizer Lithium Ultimate AAs, and maybe some AAA too for favorite AAA devices, but AA is a lot more energy/cost efficient, they're awfully expensive in AA, never mind AAA.

Is there any durability or lifetime difference specifically between unprotected and protected 18650 batteries?

mickb said:

Is there any durability or lifetime difference specifically between unprotected and protected 18650 batteries?

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A protected 18650 is just an unprotected one, with extra circuits. It's pretty hard to make the lifetime of a battery be longer, by adding circuitry, so lifetime would mostly be lower. More components that can fail, there's risk of increased self discharge, and so on. Then again, there are some cases where it could be increased, such as if used in a situation where there is no low voltage protection. An unprotected cell would discharge too low, a protected would hopefully cut off.

Bottom line is a definitive "it depends".

For the most part, it's not something I'd take into account when choosing protected/unprotected. It's a far minor difference compared to all the other differences.

excellent thanks!

sharp probes through the blister pack will allow voltage and esr measurement.

ChibiM said:

I actually answered it in my eneloop FAQ. So basically it just means that if you charge the battery for to 100% you will be able to use the battery from that initial charge 10 years later. And there should be about 70% charge left after those 10 years. See more explanation in my FAQ.

Actually I found some eneloops in Japan last week, that are from 2008/04 so I want to do a test to see how much charge is still left in them.. The package is new, unopened.... so Im a little excited to know. ... just have to wait 10 more months

Click to expand...

For long shelf life you are looking at Lithium Primary. In the AA format you can expect the following shelf life:

Zinc Chloride (heavy Duty Carbon Zinc): 2 to 4 years
Alkaline manganese: They are now claiming 10, it wasn't that long ago it was only 5.
Lithium: 20 years (it wasn't that long ago it was only 10).

Of these, let's compare costs:

Zinc Chloride: Cheaper than dirt.
Alkaline: Cheap as dirt
Lithium: A bit Pricey

Let's compare Cell weight:

Zinc Chloride: Very light, i use these in a flashlight where the lighter weight is more important than having 24 hours of runtime (this is an INCANDESCENT light by the way, but D cell).
Alkaline: A bit heavy, but not too silly unless you use then in a very light weight device.
Lithium: Very Light weight not much more than Zinc Chloride.

Leakage:

Zinc Chloride: Zinc Chloride leakage is uncommon, but still possible if cared for correctly. However, just like Alkaline they can leak at a seemingly random interval. Zinc Chloride Leakage is almost always destructive unless caught and cleaned within a few minutes of leaking.
Alkaline: Alkaline leakage is uncommon, but still possible if cared for correctly. Alkaline leakage can range from being an inconvenience (cleaning terminals and wiping up any liquid) to total destruction (contact with circuit boards or in an aluminum flashlight).
Lithium: Not much is known other than Energizer stating that under normal consumer use it shouldn't be possible.

Performance:
Zinc Chloride: Poor to Garbage: Intermittent light loads such as flashlights, radios (excluding transmitters or those with digital displays), clocks, and remote controls are ideal. Transmitters are okay if transmitter use is intermittent such as a walkie talkie. Avoid devices (other than clocks) with motors. Digital cameras must be avoided. I actually tested that, the cells lasted two shots.

Alkaline: Good to Poor: Great for most battery loads. Excellent performance in Carbon Zinc Applications (when running a portable radio with analog tuning you may be wondering when the battery will finally die). Good performance in Walkie Talkies as long as use is intermittent or transmitter power is low (anything above about 2 watts can cause cell heating during long conversations). Poor performance in heavy drain devices such as digital cameras, photoflash, 5 watt Walkie talkies, pocket televisions.

Lithium: Picks up the ball where Alkaline drops it. Heavy loads that see poor performance on Alkaline cells will see a performance boost, low drain devices will not have a performance improvement. Extra care is required in flashlights, especially of the incandescent variety as the nominal voltage is 1.7. Remember with Lithium the cut off voltage (dead battery point) is 1.5 volts under load, not 0.9 volts.