EBL 1100mAh NiMH AAAs - junk or not?

About 2 years ago when I decided to start using rechargeable AA and AAA instead of alkalines I purchased a bunch of EBL 1100mAh AAA cells, and Powerex 2700mAh AA cells, from Amazon. This thread is primarily about the EBL AAAs. The charger I got back then was an EBL-999 12 bay smart charger.

I use them in low-current applications mainly, such as digital audio recorders and LED flameless candles (especially around Christmas time). This past Christmas season I noticed on occasion a candle would fade out faster on one set of batteries than another, even though I charged them before I put them in the candles. Figuring some cells were weaker than others, I purchased the Maha MH-C9000 so I could refresh the cells and measure them.

Well, so far, most of the AAAs I've tested have measured below 80% of the rated 1100mAh. I've tried 10 so far. Two read "high" on the C9000 right off the bat. The remaining 8 that didn't read "high" gave me varying mAh values after a break-in cycle. Most are in the mid 800s. The best cell so far has been 911, and the worst around 758 (not counting one high-resistance dud that read 357 and about 2.08V on the Maha during the impedance test, just below the "reject" threshold).

Some people say that below 80% of rated, is considered a junk cell. So far, out of 10 cells I've tested, only 2 are over that amount. Part of the problem is the MH-C9000 which is optimized more for AA than AAA cells, with its pulsed 1A discharge plus it measures the voltage under the 1A load, causes the charger to terminate the discharge on the AAAs when there may still be a few more mAh in them.

Now my Powerex 2700 AA cells are great. Every one so far has been at least 88% of rated capacity. Certainly AA cells have lower internal resistance and more capacity, so the Maha can measure them more accurately, but I was hoping for a bit more from my EBL AAAs. Even the dud ones that read HIGH on the Maha charge fine in the EBL-999 and they work fine in my applications, so they aren't "bad". Maybe they don't last as long, and won't work well in a device that uses multiple cells, but as I run them through the break-in cycle I label the mAh rating on them so I can match them.

So... does anyone else have experience with these EBL batteries? Are they as bad as my initial testing is showing? I have many more to test, once I finish refreshing my Powerex AAs and the Maha chargers free up. I also have some I bought a couple months ago, which I haven't put in the Maha at all yet... I want to get through the old ones first.

There are really no 1100mAh AAAs that are worth a damn. I had 12 AccuPower 1200 AAAs that weren't close, but they did last a couple of years before they were toast.

Stick with FDK (Fujitsu/Eneloop) sourced NiMH AAs & AAAs.

Your blood pressure will thank you.

Chris

Oh well, 2 years ago I didn't know about Eneloops. I basically went with batteries on Amazon with the highest mAh rating and decent reviews (seems all brands get some bad reviews). At least the EBL-999 charger is pretty good, it doesn't appear to overcharge batteries based on the "warmth test" anyway. And now I have two MH-C9000s as well.

I'll just keep running the AAAs through the C9000s and weed out the bad ones I guess. And get Eneloops next time. Or Powerex/Imedion, as my AA 2700s are great.

I think part of the reason for the low mAh readings is the C9000 draws a lot of current in pulses and the EBL AAAs have high enough resistance that it terminates discharge prematurely.

I'm actually surprised you're batteries had that many milliamp hours. I had some ebl brand Double A's which were rated as 3000 milliamp hours and they were all under 500

kpatz said:

About 2 years ago when I decided to start using rechargeable AA and AAA instead of alkalines I purchased a bunch of EBL 1100mAh AAA cells, and Powerex 2700mAh AA cells, from Amazon.

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According to my tests normal NiMH AAA cells have around 650-750 mAh of real capacity and the high capacity AAA cells have 800-900 mAh of real capacity. The higher the capacity the lower their cycle count though...

Don't trust the nominal ratings written on the packaging. Especially when made in China with no manufacturing date printed on them...

kpatz said:

Some people say that below 80% of rated, is considered a junk cell.

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I would say below 80% of initial capacity, not rated capacity Anyway, your EBL cells look fine to me. Toss the ones with high internal resistance and keep the rest.

AA Cycler said:

I would say below 80% of initial capacity, not rated capacity Anyway, your EBL cells look fine to me. Toss the ones with high internal resistance and keep the rest.

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Thanks. I found 2 more "HIGH" cells, for a total of 4. I experimented with one, deep discharging it in a flashlight and charging on the Maha to see if it helped. It didn't, so they're in the "to be recycled" pile now.

I have a cell on break-in now that was on the high side of resistance at first, so I drained it in the flashlight, put it on the Maha and it read 2.01V on the impedance test. It finished the discharge cycle of break-in with over 700 mAh, so it's on the high side of resistance but not a bad cell capacity wise. I'm keeping track of all the vital parameters in an Excel sheet, so I can match the cells when putting them in devices, and avoid using junk cells in important places.

As for the initial capacity, I'll have a better idea on that when I start testing the cells I bought a few months ago. There's no date codes so I don't know when they were made, but the labels are slightly different (whiter with more of a matte finish instead of glossy) so they were definitely manufactured at a different time, or came from a different factory. I'll probably average out the measured ratings of those cells after break-in to determine what the "initial" mAh really is, and update my Excel sheet to reflect this.

I'm discharging a few more cells in the MH-C9000 in preparation for running break-in on them. At 300 mA they've been going for a couple hours now. I guess most EBL cells aren't junk, it's just the occasional bad banana that makes them look bad.

I guess in retrospect, the cells aren't so bad... most of them are testing well. The labeling is the issue: they shouldn't be labeled 1100mAh and they even say "low self-discharge" on them... no way, these things drop like a rock when they sit around charged. I'll have to do a test on one down the road after I've finished all the break-ins.

I bought the 700mAh AAA versions of EBL. Most of the time they stay charged but I noticed they don't work well in my weather station, though the weather station actually takes AA batteries. I didn't want to take up some of my AA Eneloops, since the station takes 3 of them but considering, I decided to use a set of Eneloops in there and see if they do better.

I bought 2 La Crosse BC1000 chargers, one a while back that came with AA and AAA batteries and well thought they were junk. The second charger i asked La Crosse if they had some sort of system to using their batteries properly, the guy told me to charge the batteries and use them and cycle them 10 times (discharging them until they get low) in a flashlight or other device I use regularly And I got about 950mAh out of 1000mAh from them which did better than when I did a break in with the AA versions. So I'm doing the same for the AA. Just use them regularly 10 times and then cycle them in the La Crosse charger. It may be the same with the 1100mAh EBLs but they probably only about 900mAh regardless. I also get about a month out of the La Crosse batteries before they are in need of a recharge as well.

I came across another high IR EBL AAA cell, (I think it was around 2.1-2.2V on the MH-C9000), but this one had quite a bit of charge in it, took a while to discharge fully. I stuck it in my flashlight and put it on to deep discharge it and then I got busy with other things and forgot it was in there, until an hour or so later I noticed the flashlight's LED was barely glowing, lol.... guess I really deep discharged it. I put it in the C9000 and it read 1.94V on the impedance check--still high but well within the level the charger will accept, so I did a brief charge and then a discharge, and it seemed to be working ok (it didn't immediately say "done" on the discharge), so I started a break-in cycle on it. We'll see if the IR stays in the lower range or if it goes high again. Maybe on the marginal cells a deep cycle will put some more life in them.

One thing to note, I never left the light on for very long. Essentially when cells are being discharged in a charger vs a device you tend to shut the device off and then on soothe drain is not consistent so if you have the light on for a few minutes turn it off briefly and then turn it on again you can actually get more energy/capacity out that way. That's why if you have drained batteries you get a few seconds or minutes of runtime before the device stops working or shows signs of low battery.

My guess is that you could get the batteries to about 40% (around 1.26v rest) and turn the light on for a couple of minutes and let it rest for a minute then repeat the process. Though in real world applications that may not work unless you are a flashaholic who likes doing that with their lights 😂. I discharged the batteries until they were about 1.22v resting and recharged them. Deep discharging (discharging the cells until they are completely dead) reduces the life cycle on the cells and high capacity cells will show signs of aging sooner so they are used best to have them recharged when they no longer provide sufficient power to the device. Just some thoughts 😁

Well, on the marginal ones it doesn't hurt to try a deep discharge. If it helps, great. If not, they'll end up in the recycle pile anyway.

EDIT: After breaking in the one high-IR cell that I deep discharged, it reported a 0 mAh capacity. It worked in my flashlight (albeit not at full brightness) when I tried it, so it's probably just the IR causing a voltage drop below 0.9V at the 1A instantaneous load. Anyway, when I started a charge cycle it reported something like 2.3V on the IR test. Another one for the recycle pile.

How far are you discharging these batteries? I try to only discharge the Eneloop Pro to about 1.1v.

The more the cells are discharged the less capacity you may have and High IR could be a result. I did these to some older cells which drastically reduced their capacity, they are junk cells but i think that discharging them too far can cause the High IR to occur in your cells. You got me curious about these cells. I can get a set for $6, but I don't have plans to order anything from Amazon until March. I am trying the method I used from what La Crosse told me to do on some crap cells that exhibit 0 mAh but will stay charged for months on end. I have some cheap no name 600 mAh AAA cells i got from a walkie that were still showing 1.26v after I can't remember the last time I charged them. Got some in a flashlight that doesn't draw too much power.

MidnightDistortions said:

How far are you discharging these batteries? I try to only discharge the Eneloop Pro to about 1.1v.

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For most of the cells, I've been discharging them on the MH-C9000 which terminates at 0.9V under a 1A load, so it's deep but not overly deep. It's possible that a few of the older cells got over-discharged in a device that sat too long, or due to mismatching got damaged due to polarity reversal. I've only messed with deeper discharges on a few of the cells that were showing a high IR and/or low mAh on discharge. At this point I've given that up since it doesn't seem to work. It sort of brought one cell to life for one cycle but that's probably because it warmed the cell up and the IR dropped until it cooled again. The flashlight I used for my deep discharges is a single-AA LED Brookstone light, using a small wad of aluminum foil between the battery and tail cap to "adapt" the flashlight to the AAA cell, thinking that it would gently discharge the cell, but then out of curiosity I measured the current draw with an AA cell and got about 2 amps. So much for a gentle discharge.

I ran discharge cycles on the new batch I bought a few months ago in preparation for running the break-in on them, (I have 4 on the break-in cycle now) and they appear to be stronger and lower IR than the older ones. I haven't had them long enough to kill them yet I guess.

Once the break-in cycles finish and I get mAh measurements on them we'll see how well newer ones fare. I'm labeling every one so I can match them evenly when using them in devices that use more than one cell.

The first set of 4 cells bought in 2017 just came out of the break-in cycle. They all have measured mAh readings between 964 and 975 mAh, and all have IR voltages below 1.6V (except one so far which measured 1.66). The good 18 cells from 2015 averaged 834 mAh and 1.85V IR, 1.69 being the lowest.

So, either (1) they improved the design or construction of the cells, (2) they degrade over 2 years' time, or (3) my EBL-999 charger is slowly killing them. I may mark one set of 2017 cells and charge those only in the EBL charger and mark another set to charge only in the MH-C9000 to see if that's a factor over time.

^^^ What sort of IR test are you dong? Normally the results are in ohms, not volts.

The impedance check the MH-C9000 does at the start of the charge cycle--it charges the cell at 2A for a few seconds and measures the voltage. The higher the voltage, the higher the cell's IR. Over 2.08 (or so) it throws the "HIGH" message. I don't have a way to measure cell IR directly in ohms... I need to get a low resistance high wattage resistor to use as a load. I may have one in the shed but it's too cold to go out and look.

If you're interested in doing your own IR measurements then you may find of interest the paper I cited here - which compares about 10 common methods.

Hello Kpatz,

My vote would be for 2, the cells degrade over time.

AAA cells don't seem to have the same quality as AA cells and they don't seem to last as long or hold up as well. A linear extrapolation would estimate that your older cells have roughly another 2 years of life left.

Tom

kpatz said:

For most of the cells, I've been discharging them on the MH-C9000 which terminates at 0.9V under a 1A load, so it's deep but not overly deep. It's possible that a few of the older cells got over-discharged in a device that sat too long, or due to mismatching got damaged due to polarity reversal.

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Probably got cell reversal or at the very least was over discharged in a device. Some devices will continue to suck any energy out of a battery significantly reducing the cycle life. So if you are getting high ir like over 2 volts on the C9000 charger the cell is considered junk. They still may be useful but won't keep the device running for very long unlike a new battery would.

Out of the 25 cells from 2015, 5 were HIGH and rejected by the C9000, 2 are marginal with low tested mAh (357 and 588), and the remaining 18 have a minimum of 719, a maximum of 967 and an average of 834 mAh. Two of these have 2V IR, the rest average 1.83V. Only 4 cells measured over 900 mAh.

Out of the 20 cells from 2017, one cell is slightly weaker compared to the rest (1.66V, 813 mAh). The remaining 19 range between 950 and 979 mAh (avg 967) and average 1.55V on the IR test.

So, the new cells are pretty good. But my 2 year old cells are much weaker. Maybe a combination of age and some "usage abuse" (over discharging or cell reversal). Hopefully now that I have them all labeled I can avoid the latter at least by matching them in devices, and by keeping a spreadsheet I can monitor how the cells perform over time.