Anyone done Self Discharge tests on Eneloop Pros?

[ChrisGarrett]

no, the Ladda have been in 7 weeks with no change in performance from new. I said after a few weeks eneloop and energizer aaa Nimh are getting weak. As in aimed right at the sensor or real close to work. I can point the remote at the wall 180 from the tv right now with 7 week in the remote Ladda aaa cells and it works perfect. The weak cells are swapped when they need direct aiming. Not when they are completely dead.

IKEA doesn't make NiMH batteries and those that they sell, are sourced from China and from Japan.

So how would you account for this discrepancy?

Do you think that IKEA is somehow skimming the cream off the top, when it comes to the manufacturers, be them Chinese, or Japanese in origin?

I think most of us are in agreement that the FDK plant in Japan, now owned by Fujitsu, is making the state of the art NiMH batteries and while Panasonic has manufacturing plants in China, making NiMH Eneloops, they don't possess the technological patents that Fujitsu now holds.

I've used Chinese batteries, Taiwanese batteries, and Japanese batteries, even some Sanyo HSDs back when Sanyo was still the owner of the technology and while they worked, they all died after 2-3 years.

Chris

 

[MrAl]

Hi,

Just a quick note about the self discharge tests.
This test has to be done under controlled temperature conditions. The higher the temperature the more self discharge. Over a somewhat longer period of time this makes a difference. If someone tests theirs at a temperature of 70F and someone else tests theirs at 90F that's quite a bit of difference after 6 months.

 

[cave dave]

I just did some long term storage self discharge tests on Panasonic Eneloop Pro and Duracell DuraLock. I had originally planned to do 1 yr and 2 yr self discharge test, but I had put these away 2+ yrs ago when I moved and forgot about them. I have some more tests coming, including Eneloop XX and Eneloop AAA, but will post them all in a separate thread.

Notes: They were in an Air conditioned space the whole time 78-80 deg in summer, cooler in winter. The numbers in (##) are my codes for the cells.

Test 1: 3.5 yr. Self discharge test:
Charged with a Break-In cycle charge on Powerex MH-C9000
Charged on 31 Jan 2015, Discharged on 2 Aug 2018

Results:
2pcs Eneloop Pro AA min.2450 mAhBK-3HCCA (Date code 14-05 LN)
(EP4) = 1924 mAh
(EP5) = 1919 mAh

2pcs Duracell DuraLock AA 2400 mAh (aka Duraloop Pro)
(DP1) = 1666 mAh
(DP2) = 1665 mAh


Test 2: ~ 2 yr 1 mo. Self discharge test:
Charged with a simpler 1000mA charge on Powerex MH-C9000
Charged on 25 June 2016, Discharged on 4 Aug 2018

Results:
2pcs Eneloop Pro AA min.2450 mAhBK-3HCCA (Date code 14-05 LN)
(EP1) = 1984 mAh
(EP3) = 2002 mAh

2pcs Duracell DuraLock AA 2400 mAh (Duraloop Pro)
(DP3) = 1683 mAh
(DP4) = 1687 mAh


Then I recharged all with a Refresh Cycle (1000mA/500mA Charge-Discharge-Charge) and measured discharged capacity in that cycle as:

(EP1) = 2477 mAh
(EP3) = 2494 mAh
(EP4) = 2488 mAh
(EP5) = 2471 mAh

(DP1) = 2316 mAh
(DP2) = 2327 mAh
(DP3) = 2250 mAh
(DP4) = 2249 mAh

Conclusion: This era DuraLoop and Eneloop Pro are not the same. Eneloop will take more initial charge and will also have more capacity after 3.5 yrs. :twothumbs. The Duraloops are pretty good though and were about half the price and at the time I think I bought them locally at Target. Not sure if you can still find them or if they have switched manufactures.

Note: I've had poor results with other "re-branded 'loops" like Amazon Basics and the Chinese LSD cells so can't recommend them for critical applications.

 

[keithy]

I just did some long term storage self discharge tests on Panasonic Eneloop Pro and Duracell DuraLock...

Thanks cave dave. That's exactly the data I was hoping someone would have done. That seems to be closer to my recollection of Eneloop Pros self discharge rates. Yours showing 80% after two years is quite good, but over 75% after 3.5 years is really good.

I am glad I'm not the only one who does these, and my method of marking the cells and the sticky note in the battery box looks almost the same as your method.

I am now onto testing a third set of Ikea Ladda Whites - stamped "1804" so made in January, 2018 for long term self discharge testing. I will check two of them next year in June 2019 for the 12 month test, and the next two I will check in June 2020 for the 24 month test.

The other earlier 2x4 sets of mine were made in "1637" so made in September 2016 that I have already done two 6 month self discharge tests on. They have been discharged and recharged again, and I will do the same 6 month and a 12 month test on a pair of each.

Preliminary Conclusions Ikea Ladda White Self Discharge Rates
From my two of my 6 month discharge tests were showing Ikea Laddas at between 65%-70% of capacity and SweD's tests of his Ikea Ladda Whites, http://www.candlepowerforums.com/vb/showthread.php?448723-IKEA-Ladda-6-months-test-of-SoC showing about 72%-73% after 6 months.

While this is a fairly small sample, they are across various production batches, and it does appear that the Ikea Ladda Whites are not exactly as Eneloop Pros where self discharge rates are concerned. The Ikea Ladda Whites have a greater self discharge rate compared with Eneloop Pros.

 

[cave dave]

Added test results:

Test 3: 2yr 1.5 mo. Self discharge test:
Eneloop AA, Dark Blue regular HR-3UTGA, circa 2012:
Charged 16 June 2016, Discharged 31 July 2018
(DB1) = 1563 mAh
(DB2) = 1553 mAh

Test 4: 2yr 1 mo. Self discharge test:
Charged with a Break-In cycle charge on Powerex MH-C9000
Charged on 08 July 2016, Discharged on 6 Aug 2018

2pcs AA Eneloop XX, min 2400mAh, HR-3UWX (Date code 11-06 LL)
(XX1) = 1719 mAh
(XX2) = 1739 mAh

4pcs AA Duracell LSD 2000 mAh, made in Japan (pre-DuraLock)
(DL1) = 1420 mAh
(DL2) = 1432 mAh
(DL3) = 1432 mAh
(DL4) = 1501mAh


Unfortunately, I didn't put sticky notes with charge dates on all of the sets. So I have results for other batteries without the charge dates:

Unknown time frame results, but at least 2 yrs in storage:

Test 5:
Duralock AAA, 850 mAh >2yr:
693 mAh
701 mAh

Test 6:
Eneloop AAA light green 2012 model, min 750 mAh >2 yr
(LG1) = 624 mAh
(LG2) = 641 mAh
(LG3) = 647 mAh
(LG4) = 643 mAh

Test 7:
Eneloop AA, Light Blue regular HR-3UTGA, circa 2012:
not sure on charge date, over a year maybe more

(LB1) = 1687 mAh
(LB2) = 1686 mAh
(LB3) = 1684 mAh
(LB4) = 1704 mAh

I have some June 2016 charged AAA pros, and white AAA eneloops coming next.

 

[ChibiM]

Thanks Cave Dave..very useful to have that data. I might like to add that to my website in the future. If so I will ask you for permission.

 

[cave dave]

I added test 7 above.

I have notes somewhere from 3.5 yrs ago documenting 6mo and 1 year tests I did on the Pro vs Durapro cells pictured above. So when I find them I can add them in.

Other notes:
I had labeled cells that received some sort of mistreatment. For instance a white AA eneloop that I had dropped on hardwood and a Duraloop pro that I had over-discharged in some device down to about 0.15v. So far neither of those events seemed to impact the long term performance of those cells. :twothumbs

When I am done with the long term storage tests, I have some Eneloops in remotes, clocks and stuff that I will do a cycle on. The ones in a remote are labeled as weak performers (1611mah, 1532mah) from a refresh cycle (been in use since 2006).

 

[cave dave]

Another test, this time on Eneloop Pro AAA

Test 8: ~2yr 1.5 mo - Self discharge test:
Charged with a 500mA charge on Powerex MH-C9000
Charged on 19 June 2016, Discharged on 8 Aug 2018

4pcs Eneloop Pro AAA, min 900 mAh, BK-4HCCA (Date code 14-01)
(p1) = 707 mAh
(p2) = 651 mAh
(p3) = 713 mAh
(p4) = 688 mAh


Next up: Since the last time I bought Eneloops was 2014 I decided to refresh the stock. Some of my knockoff China made LSD cells that I use in remotes, calculators, wireless keyboards/ mice are starting to fail so I want to replace those with my older real eneloops which are still doing fine. I ordered some new Eneloops using Chibi's eneloop101.com link to Amazon. They arrived yesterday with 2018 manufacture dates. I'll test the out of package capacities.

 

[ChibiM]

Aswesome Cave Dave!
Looking forward to the data!

 

[cave dave]

I found 6 pages of notes like below from various tests like 1mo, 6mo, 1yr tests and some out of the package tests.

I also found 3ea 2006 AA eneloops in a dead LCD weather clock. They were drained to 0.01v, 0.05v, 0.78v

They seemed to have charged up just fine on a 1000mAh charge and they will be in a discharge cycle in an hour. Let's see if they survived. Don't try that with LiIon!


*** EDIT - Update ***
With the refresh cycle on the "over-drained" white 2006 AA eneloops the discharge capacity was:

6-1) Drained to 0.01v, test discharge = 1723 mAh
6-2) Drained to 0.05v, test discharge = 1673 mAh
6-3) Drained to 0.78v, test discharge = 1593 mAh

Not what I expected from the voltage readings. Those are still usable cells if they still have LSD. I think I'll cycle them or do a forming charge and then let them sit for a month to check there LSD abilities.

 

[ChibiM]

Thats kind of funny.
I would image the other way around, the one with the most voltage would have the most mAh.. But i was wrong. Interesting stuff.

 

[cave dave]

Test 9: Eneloop AA, Unknown Storage time, two cells were marked as "weak" from previous tests.

4pcs Eneloop White AA, circa 2006
(9) = 1673 mAh
(10) = 1485 mAh (previously marked as weak)
(11) = 1648 mAh
(12) = 1242 mAh (previously marked as weak)

Test 13: Rayovac Hybrids AA that were just laying around the last two years. Marked as known poor performers

RH1) 0 mAh 0.09v
RH2) 0 mAh 0.08v
RH3) 0 mAh 1.14v

Did a refresh cycle:
RH1) refused to charge (high impedance)
RH2) 2167 mAh
RH3) 234 mAh

Note: The Rayovac Hybrids (made in China) have never impressed me. If you can get them cheap they are OK for remotes and calculators, but they don't have the durability or LSD of real eneloops.

That is the last of the stored eneloops the next set of tests are 'loops in various devices (clock, remotes, etc), and some brand new 2018 cells.

 

[cave dave]

Some tests from LSD cells inside various devices (clock, etc) below:

Test 10: Duracell Duralock AAA 850mAh, stored inside PT EOS headlamp for at least two years
Note: EOS has small vampire drain, and may have seen very brief usage.
Unknown charge date (>2yr), Discharged 11 Aug 2018.

1) 373 mAh
2) 387 mAh
3) 376 mAh

Note: The EOS vampire has sucked half the juice out!


Test 11: Eneloops in a LCD clock for almost two years
White 1st gen Eneloops Circa 2005 and 2006
These were fast charged (1000mA) in October 2016 and seemed to be powering the clock just fine. Discharged 12 Aug 2018.

2005-1) 262 mAh
2005-2) 209 mAh
2006-3) 225 mAh

Note: The clock needed a recharge, but would have probably gone another couple months for the full two years. :twothumbs I have these on refresh cycle and will update this post with discharge cap when done. These are some of my oldest eneloops. There are others around from 2005 but I can't find them.

Test 12: Rayovac Hybrids AAA in scientific calculator (H2, H3, H4) and a Lumintop worm (H1) recharged 11 days ago (known poor performers)

I knew these cells were bad, I have them at work and they used to run the calculator for a year and now only last a couple months. I charge these on the cheap white eneloop charger that came in a packed in a set from ~2006
Charged on 30Jul2018 and discharged on Discharged @ 200mA on 10 Aug 2018. (11 Days)

H1) 0 mah
H2) 409 mAh
H3) 0 mAh
H4) 337 mAh

Note: The PowerEx refused to charge H1 and H3, they gave a high impedance warning. I put them on the Xtar and that at least that tried to charge them, but H3 couldn't take a 200 mA discharge and immediately went below 0.9v and stopped on the Powerex.

After a couple charge discharge cycles I am getting:
H1) 356 mAh
H2) 533 mAh
H3) Won't take a charge
H4) 520 mAh
I am guessing these have also lost there LSD capabilities. I'm going to try a forming charge later on these, I threw H3 in the trash and the rest may follow, although they still do power that calculator for a couple months

 

[cave dave]

Bought some Brand New 2018 Eneloops from Amazon

Eneloop AA, Discharge straight from package, note factory charge is reported as 80%
BK-3MCCA, min 1900 mAh, Date Code 18-03 YF

18-1) 1393 mAh
18-2) 1397 mAh
18-3) 1387 mAh
18-4) 1383 mAh
18-5) 1388 mAh
18-6) 1395 mAh
18-7) 1388 mAh
18-8) 1381 mAh

** updated this post with 8ea AAA

Eneloop AAA, Discharge straight from package, note factory charge is reported as 80%
BK-4MCCA, min 750 mAh, Date Code 18-04 OH

AAA-1) 555 mAh
AAA-2) 556 mAh
AAA-3) 562 mAh
AAA-4) 554 mAh
AAA-5) 558 mAh
AAA-6) 558 mAh
AAA-7) 554 mAh
AAA-8) 554 mAh

 

[ChibiM]

Wow, just wow!
Thanks for all the tests. I actually had a clock that I did a test on with an eneloop Lite vs standard eneloop. The eneloop Lite took exactly 1 year (maybe a few days difference) and the standard eneloop exactly 2 years...

ps. where did you get the 80% charge from factory from? I've never seen them mentioning 80%!

 

[cave dave]

...

ps. where did you get the 80% charge from factory from? I've never seen them mentioning 80%!

I thought that was just well know CPF folklore going back all the way to 2006. :thinking: I have also seen the number 75% thrown about. All testing seems to show that somewhere in that range seems to be the case.

Edit: My personal theory is that the factory does that so that if one were to throw them on a charger straight from the package the cells would have a chance to charge and warm up a bit and get a good clear dV/dt termination signal. If they were fully charged in the package then some chargers might not get a proper termination signal and would try to overcharge the cells.

My other theories are they charge then discharge some at the factory to test voltage characteristics as part of a QA process, or that its just cheaper and quicker to charge them to 80%.

 

[cave dave]

I updated above with New 2018 AAA out of the package results.

Thats kind of funny.
I would image the other way around, the one with the most voltage would have the most mAh.. But i was wrong. Interesting stuff.

I have a theory about this. The powerex is only reporting mAh not power or voltage (you can view volts at any point in time, but I don't want to stand there and record it every min for 5 hrs). I think on the low voltage, possibly damaged cells there is higher impedance and the voltage is suppressed. So while they go longer, there is less voltage during the run, so overall less power output in Wh. This is just a theory since I don't have the right equipment to monitor the voltage during the discharge run.

 

[ChrisGarrett]

I thought that was just well know CPF folklore going back all the way to 2006. :thinking: I have also seen the number 75% thrown about. All testing seems to show that somewhere in that range seems to be the case.

Edit: My personal theory is that the factory does that so that if one were to throw them on a charger straight from the package the cells would have a chance to charge and warm up a bit and get a good clear dV/dt termination signal. If they were fully charged in the package then some chargers might not get a proper termination signal and would try to overcharge the cells.

My other theories are they charge then discharge some at the factory to test voltage characteristics as part of a QA process, or that its just cheaper and quicker to charge them to 80%.

I've not been here as long as you, so I'll defer to your experience, but I've often read 70% solar charged.

Regardless of the number, these 'pre-charged' batteries are labeled as such, so one can use them out of their pack and get a reasonable amount of usage before charging.

With HSD batteries out of their packs, one is probably closer to 0, after a few months of sitting on the shelf, vs. 70%, or 80% for the LSD offerings.

Of course, discharge current with be the final arbiter of what true capacity is left, out of the pack.

These were 38 month old, out of the pack, Gen. 2 Glitter 5 Year Anniversary Eneloops discharged at 300mA:

http://www.candlepowerforums.com/vb...oop-5th-Anniversary-GLITTER-AAs-38-month-test

Chris