Disappointed with CTA AA 2700mAh Ni Mh batteries

[kirby]

I bought a pack of four CTA AA 2700mAh Ni Mh batteries over a year ago when I bought some camera equipment from an online site in USA. This is what it looks like. http://ctadigital.com/catalog.asp?m...&parentid=15&categoryid=71&groupid=71&id=1614
They are sold in many outlets.

I opened it for the first time a few days ago. Ran through the break in cycle in Maha C9000.
I got 1432, 1488,1615,1544 mAh respectively.

I then ran them through the Refresh-analyze cycle and got
1444, 1571,1588, 1533 mAh respectively. Not much change at all.

Is this what I supposed to get from this Chinese manufacturer? At Thomas Distrubuting they are only $2 cheaper then Powerex and Sanyo brands for a pack of 4. I know it won't be as good but I am certainly expecting at least 2000mAh out of those batteries. How disappointing.! :thumbsdow:thumbsdow

Maybe I should run through a few more cycles and see?

I was thinking of getting some 12000mAh D size of this brand but I think I should give it a miss now. http://ctadigital.com/catalog.asp?m...&parentid=15&categoryid=71&groupid=71&id=1606

 

[Aussie Cheese]

whilst i have never tried them, i always thought that CTA was a decent brand. while TD wont put their opinion of these cells on the website (unlike batteryjunction) it doesnt hurt to give them an email to get it privately.

thanks for the info

ps:

lol even they sell "1200mAh" AAAs but the description is only 850mAh :thinking:

 

[Turbo DV8]

I bought a pack of four CTA AA 2700mAh Ni Mh batteries over a year ago... I opened it for the first time a few days ago. Ran through the break in cycle in Maha C9000. I got 1432, 1488,1615,1544 mAh respectively.

There's your problem, right there. You bought a non-LSD NiMH cell that had been sitting in it's package for who-knows-how-long, then you waited over one more year to finally open it and use it, and now you're surprised that the cells are toast? The cells were long ago completely discharged just from sitting unused, and now they are permanently damaged. NiMH cells do not take favorably at all to being stored below about a volt for any period of time.

On the other hand, I purchased some "11,000 mAh" CTA D cells once, and they barely lived up to 9000 mAh. So I am of the opinion that CTA mAh ratings are to be taken with a box of salt.

 

[kirby]

There's your problem, right there. You bought a non-LSD NiMH cell that had been sitting in it's package for who-knows-how-long, then you waited over one more year to finally open it and use it, and now you're surprised that the cells are toast? The cells were long ago completely discharged just from sitting unused, and now they are permanently damaged. NiMH cells do not take favorably at all to being stored below about a volt for any period of time.

Thanks.

Anyone else concur? Any other views/opinions?

Not sure if they were completely discharged. I should have measured the voltage prior to putting them through "break-in" in the Maha C9000. It took two days or more to go through that "break-in" cycle.


I am now putting the batteries through three "cycles" (not the "break-in" one) and after that another "Refresh-analyze cycle". Shall see what the readings are.

 

[koala]

CTA is a good brand, for rechargeable Lithium-Ion it is, I use them for my camera. I would buy well proven NiMHs. CPF has a extensive data on these.

 

[SilverFox]

Hello Kirby,

A while back I purchased some CTA 2400 mAh cells that had almost the exact capacities that you listed...

Perhaps they re-labeled those to 2700 mAh...

Tom

 

[kirby]

Thanks.

I am now putting the batteries through three "cycles" (not the "break-in" one) and after that another "Refresh-analyze cycle". Shall see what the readings are.

After the above the figures are even worse

1341, 1431, 1398, 1395

 

[Turbo DV8]

After the above the figures are even worse

1341, 1431, 1398, 1395

They were allowed to stay fully discharged too long. Again, they are toast. Don't perform any more refresh cycles on them. Let them die with what little dignity they have left. Show some compassion, man!:mecry:

 

[TorchBoy]

Re: Disappointed with CTA AA 2700mAh NiMh batteries

Anyone else concur?

I've never heard of the CTA brand before but it really doesn't sound good for non-LSD cells to be left a year after buying before being charged. It's definitely not something I'd recommend.

 

[kirby]

:mecry: :mecry::mecry:

 

[TorchBoy]

I feel for you. I'm in the process of finding out that a 6V SLA gel cell can't be left connected to a 100W bulb for a week and still be expected to work. :sigh: