NiMH comparison - 1 year test

Looks like the eneloops got beat a little by the all the rebrands: duracell, energizer, amazon basics, and laddas, when it came to low self discharge after 1 year….even got beat out by the non eneloop rebrand ROV cheapies……so much for the theories that FDK puts some secret ingredient in eneloops that makes them self discharge less than the other cells made in the same factory with different wrappers, I guess?

Out of curiosity I went and compared his capacities after a year of use with my tests

I did not test the Rayovac and Harbor cells and the Duracell can be different…

It’s nice to see multiple tests confirming the same results…

Cheers,
AA Cycler

My oldest Eneloops are from 2006, so about 13.5 years old. I have 8 of them. I ran a capacity test on all of them just last week. They average just under 1800 mAh. New Eneloops I tested are around 1950 mAh. So, about 8% capacity loss after 13.5 years. Not bad!

The lowest one tested at 1450mAh. It was much less than all the others. So, it appears to be dying, at least for higher drain stuff. But it still works fine for lower drain.

I can’t accurately measure internal resistance, but the charger does show the old Eneloops do have significantly higher IR than new Eneloops. That appears to be the biggest issue with aging.

All 8 of those old Eneloops still appear to hold their charge fine, so low-self-discharge doesn’t seem to be affected much.

Those Eneloops have probably been cycled 200-300 times, mostly partial discharges. So, not really heavy use, but not light either.

One thing I don’t understand in that video…

At the 5:30 mark, he appears to test the voltages of his batteries after being in storage for 1 year. They all seem to be under 1.20v. WTF??? Even the Eneloops are only 1.16v after just 1 year in storage?!?

That doesn’t match with my experience at all. I find that voltages tend to settle at about 1.32v after a few months, and pretty-much stay there indefinitely. Way longer than a year!

Something isn’t right with his measurement, or he stored them mostly discharged (but that doesn’t seem to be the case from his capacity measurements). Anyone know what’s going on?

Or we should finally call those FDK rebrands for what they trully are, FUJITSU, while most of the Panasonic Eneloops (apart from some for EU and North America market … made by, again, FDK/Fujitsu) are made in China in their own factory anyway.
Panasonic does not own ex Sanyo FDK plant and the technologies, Fujitsu does.
I am wondering for how many decades we will repeat this mantra about all those batteries being eneloop repack.

True, that ^

Since Sanyo was bought by Panasonic, FDK’s Fujitsu became the primary brand and Eneloop just another re-brand.

I actually have a preference for Fujiloops over Japanese Eneloops, not so much that I think FDK makes them any better, but simply because they seem less likely to be counterfeit and I don’ have to worry about getting lower performing Chinese Eneloops should something change in Panasonic’s supply chain. Plus I can usually get Fujiloops at a lower price.

The only thing that surprises me a little about the tests in the video, is that the high capacity cells did better when it came to low self discharge and just as good if not better for low IR - which goes against a lot of chatter on the forums (usually with no real testing to back it up) that the high cap cells are not as good in these regards as the standard “eneloops”.

Maybe they are Voltages under load?

Quick question. Are rechargeable batteries worth it for low drain devices such as clocks and TV remotes and the like?

Did project farm do a refresh cycle when testing for capacity after the 1 year in storage?

AFAIK, I think it’s just the Asian market that gets the Chinese Eneloops. Every Costco order I’ve made (including last month), have been Japanese Eneloops.

But that brings up a good question: what version of Eneloops is he testing? Chinese or Japanese? Generation?

Yes, that makes me suspicious of his testing. There’s no way that high-capacity cells have lower self-discharge than their lower-capacity counterparts. That’s the entire point of “regular vs pros”.

Even if that’s the case, those voltages are still low, unless the load is high. But I suppose it’s possible, although it would be kind of weird for him to list voltages after storage that way. Given the amount of time and effort he put into this testing, you’d think he could measure them with a DMM.

I’m not calling his video B.S., but there’s something about his testing that we’re not being told. His capacity numbers I can believe, but not some of the other stuff. I’d like to see his results reproduced by someone else. Specifically around self-discharge, and voltages (which is definitely wrong if they’re not under load).

Pointer please?

IMO, they absolutely are worth it. New LSD type keep their charge pretty well, AND THEY DON’T LEAK!
I’ve had way too many electronics ruined by alka-leaks.

I get them when they go on sale at newegg.

He clearly states which cells are Japanese in the vid and there are no “generations” in the way they are touted around the internet, according to Eneloop, there are only normal incremental improvements made over time.

Can you link to independent tests that support this?

He shows the Voltage readings on his charger in the vid; if you have questions about his testing, why don’t you ask him?

Again, please link to the testing that refutes the “definitely wrong” results in the vids.

There are some significant advantages in later generations:

1. Cold weather performance is improved (from –10 to –20). I verified Panasonic’s claim about that, when using 1st gen Eneloop in an outdoor weather station. In extreme cold, they wouldn’t work. I replaced with 2nd gen, and they work fine in extreme cold. So they did something to improve that.

2. Lower self-discharge.

3. More cycles (though, not as many as they claim, since they use partial cycles). Plenty of tests over on cpf to verify that.

Panasonic states that. It’s ridiculous to think that they would intentionally talk-down their own product. Other than this one dubious youtube claim that is counter to all other claims, can you link to some independent tests that shows Panasonic is lying? Why do you think Panasonic wants us to think their high-capacity cells are worse than they really are? Are they trying to get people to buy their lower-priced regular batteries, in hopes that they will make less profit?

I have quite a few IKEA Laddas. In Canada they’re half the price of Eneloops. A great value.

I still favor the Japanese Eneloops. I value longevity and I’ve heard so many reports of them remaining solid after 10 years of use or neglect. That’s real value.

Take your magnifying glass with you if you buy new Duracells. The last 2 packs I got from Sams Club say made in China.