Powerex 2700's

I bought eight of these a while back and they never been up too par. What i like to do with new cells is to run 2 cycles of charge and discharge to free up the cells electrolytes, I then let the cells rest for 2 hours and run a R/A on the cells, once that is done i write the capacity of the cells down to see if the break through cycle is close to the previous cells capacity that i got on the R/A cycle. Well lets just say that the cells never met the recommended capacity of 2500mah min so i sent Maha an email about my rated capacities and how sucky the cells were, the CS was great and all he asked me was to email him my address and i got 8 new cells a week later. Ran two cycles of charge and discharge and let the cells rest for a day, ran the R/A and this is what i got. Going to do a Break-In tomorrow to see if they get to the actual min capacity. The set of cells that was sent too me are doing so much better then what i had previous.

But the best of them now (2-4 years of light-no use) can't manage 2000mAh. Have left 4 of them to trickle charge since Saturday night, will discharge them now to see what I can get out of them. The Powerex cells should be a lot better quality. All cells at around 1.385V, topping off at about 250mA for a few minutes just to make sure they have as much charge as they can possibly hold. Discharge rate 560mA so let's see how they do. When they were new ran 3 test cycles on them. Averages were: Call 1 2317, cell 2 2072, cell 3 2471, cell 4 2407.

They have not improved.

In fact it is recycling box time.

Cell 1 used to be 2317 - is now 1342

Cell 2 used to be 2072 - is now 1343

Cell 3 used to be 2471 - is now 1252

Cell 4 used to be 2407 - is now 1237

These cells have always been treated gently and are now being rejected by picky chargers as junk cells. Shows just how much better Eneloops are. My eneloops have seen far more use and most of them give better than rated capacity after over a year.

My previous cells never made the capacity minimum.....The CS guy asked me if they have been cycled and broke in and of course i said yes....i ran 3 breakins but the cells would never get over 2300mah. And for me the best part was when he told me to keep the cells. Ill use the other cells for nightlights and things like that since they still have life in them.

Yes i know what you mean about the eneloops.....im going on 3 years for the sets that i have and they still break over 1800-1900 mah......which to me is good considering.

Best reason to avoid the high capacity stuff. Never works as rated and self-discharges like crazy. Need fiddling with just to keep them working. And after all that, they don't live long.

Only LSD cells for me in future. The "extra" capacity isn't worth the grief.

Doubt any of these will last like the still working 26 year old hard used NiCd D cells I have. OK, only about 3 of the original ten still are usable but it's still a pretty impressive life span and two of them still give over their rated capacity (4,000mAh)

Now those are some awesome cells to have lived this long. Well the reason for the high mah is once off the charger they will get used mainly for nightlights.

1751 1848 1831 1551

These are all toast. Remember they are supposed to be 2700mAh and have never been hard used.

Well i would just keep them for other uses......just as long as there not dead-dead.

That sucks! I just bought 4 more of these along with a dozen eneloops.

Oh well......Live and learn right?

Just dont drop them on concrete or hardwood floors as the internals are fragile......as of now with my old cells i get about 2100mah-2300mah which is good for the applications that im going to be using them in. High Capacity cells are good when and if there going to be used right there, other then that i would really stick to lsd's.

Oops. At any rate, welcome to the site fishinfool! A pleasure to have you here.

I'll just use them until they die and luckily I have a bunch of eneloops to use in everything else.

When was the last time you did an R/A on the cells.

One set (of 4) I got just a few days ago and the first set probably not since January. I guess it's due for one right? The first set I still have to do a break-in period on them as soon as I'm done with the eneloops. I'm really thinking about getting a second C9000 but I'd rather get my first real flashlight first.....when I finally figure out what I want. lol

Glad to have you here fishinfool. Hope you enjoy your time. I'm just going to relegate these to the "beater" cells that get used for things like cordless mice - at least if they'll fit. 2700mAh cells tend to be a bit on the big side for many uses. Several of my lights won't take them.

Thanks Don! I love this forum! Other than for my dslr flash, they are perfect for remote controls which we have at least half a dozen or so at least. lol

Thats the only thing that sucks about high capacity cells.......for me i use Energizer 2450's and they seem to last, they would last longer if i was to turn the mouse off. You can also check out Dons charger setup as well as mine.

Well i let the cells rest and this is what i got....i didnt number them because i only do that after break-in. Cells came off the charger at 1.45 volts and the charge and discharge are set the same. I already see that i have three cells with the same mah so far, so im looking forward to the break-in numbers.

1. 2448

2. 2462

3. 2448

4. 2473

5. 2494

6. 2467

7. 2482

8. 2448

After reading a couple of threads concerning PowerEx 2700 NiMH batts I thought I'd add my 2 cents worth. I have 22 of these batts that were bought (from Thomas Dist.) in April 2007. I used these batts in my digital cameras & in flashlights. The use was irregular in both the cameras & the flashlights. Although I would occasionally grab my camera bag without checking the condition of the batts I never experienced any 'dead' cells.

I used a MAHA MH-C401 from the time the cells were new until April of this year when I bought a PowerEx MH-C9000. I have since run one 'refresh/analyze' cycle & one 'break-in' cycle. Using MAHA's stated minimum capacity of 2500 mAh I came up with 14 batteries @ 2500/2600 mAh, 7 batteries @ 2400/ 2499 mAh & 1 dud @ 2371 mAh. Except for the dud this is less than 2% variation from 2500 mAh.

I have since bought some Imedion LSD AA & AAA's but I don't have any numbers on them yet. I'll post some numbers when I do a 'break-in'. Right now I'm doing the second 'break-in' on some older Ray-O-Vac 1800's, the first one don't look so goodFrown.

Mike

Cool keep us posted when you can man.....