Maha Powerex 2700 mAh fail to work in cold

[etc]

OK I have a GPS with 2xAA and I use 2700 mAh Powerex cells with great success, in everything.

I keep it in the car. Turn on the GPS, nothing. Again and again. Hm... I thought the cells were fresh.

Take out the spare Eneloops I have under the seat in the emergency box, put them in - they fire right up. Double Hm..

Take the Powerex cells inside, measure their voltage, they are good at 1.33V. I never used them since I charged them 2 days ago.

Conclusion: In 30F temperature, Eneloops work but Maha doesn't?

(1.5 year old Powerex cells with enough cycles on them)

 

[Hooked on Fenix]

Most NiMH batteries don't work well or at all in cold weather. Eneloops actually say on the packaging that they work down to about 23 degrees F. They can be stored even colder. I used Eneloops in my PT EOS headlight on a backpacking trip in the Sierra Nevadas in the snow at about 12,000 feet last month. They worked fine and I would guess that it got into at least the 20s at night. It was cold enough for my wet boots to freeze solid. The Maha batteries wouldn't have worked at all in those conditions. The problem isn't your batteries. It's that your batteries aren't rated for the cold. Stick with Eneloops in cold weather.

 

[etc]

Wow, dude, that's a major discovery that makes me totally reassess my planning. I am glad I found this out now instead of later, in a situation.

It's Eneloops for me from now on!!

 

[ampdude]

I have some of the MAHA Powerex 2700's and I'm not at all impressed with them.

My old Energizer 2500's and Sony 2500's worked better and were more reliable.

I had originally purchased some Maha IMEDION nimh low self discharge batteries.

But they were so worthless in my digital camera that I had to exchange them for the Powerex 2700's.

 

[Hooked on Fenix]

Most of the higher capacity batteries I have used ended up failing prematurely from developing a high self discharge rate that made them useless and a waste of power to charge. Many of these batteries developed this problem after as few as 10 charges. If you have 2700 mA batteries that have lasted a year and a half and still work, don't get rid of them. Use them, but only in warmer weather. You got some of the few good high capacity batteries available. I have had over 50 cells fail in the last year, most of which were Energizer 2500s and Duracell 2650s (both are made by Sanyo). I have been using Eneloops since they became available and none have failed yet. Needless to say, I don't buy the high capacity batteries anymore. I use Eneloops, Rayovac hybrids, and some large lithium ion cells for certain lights.

 

[StarHalo]

No rechargeables in very hot or very cold conditions

 

[etc]

On a slightly different note, I was waiting for the release of higher capacity 18650 Li-Ion cells (2500 mAh) and now I fear they will fail more often than 2200 mAh that are currently available.


Is this a valid concern or is it totally inapplicable?

 

[Mr Happy]

On a slightly different note, I was waiting for the release of higher capacity 18650 Li-Ion cells (2500 mAh) and now I fear they will fail more often than 2200 mAh that are currently available.

Is this a valid concern or is it totally inapplicable?

It certainly seems possible, doesn't it? If you want to squeeze more into the same volume, parts have to get smaller, thinner, more fragile.

 

[madcat]

I have some of the MAHA Powerex 2700's and I'm not at all impressed with them.

My old Energizer 2500's and Sony 2500's worked better and were more reliable.

I had originally purchased some Maha IMEDION nimh low self discharge batteries.

But they were so worthless in my digital camera that I had to exchange them for the Powerex 2700's.

Can I ask you why Imedion batts are worthless in your digital camera?

 

[bob_ninja]

...
I keep it in the car. Turn on the GPS, nothing. Again and again. Hm... I thought the cells were fresh.
...

If at all possible don't keep them in the car. I use LSD AAAs in a light when working outside clearing snow, but keep them inside, warm. They work just fine outside between 0F and 32F for an hour or so. As they cool down and loose charge they start blinking, indicating low power.

In the past when NiMH were outside they wouldn't work much if at all.

 

[coppertrail]

I have some of the MAHA Powerex 2700's and I'm not at all impressed with them.

My old Energizer 2500's and Sony 2500's worked better and were more reliable.

I had originally purchased some Maha IMEDION nimh low self discharge batteries.

But they were so worthless in my digital camera that I had to exchange them for the Powerex 2700's.

I find this surprosing. The Powerex 2700s are the best cells I own. Consistently showing capacities over 2700 mAh with a low self-discharge rate for standard LSD cells. They're the only non-LSD cells I would buy at this point. My Sanyo 2500 cells were terrible, the Powerex 2500s in the same league as the 2700s in my book.

 

[Cemoi]

Stick with Eneloops in cold weather.

Is this specific to Eneloop, or does it apply to all good LSD batteries?

 

[ampdude]

Can I ask you why Imedion batts are worthless in your digital camera?

My Kodak camera's flash drains the batteries at 2.0 amps when it's charging. With the Imedions I would get a red light from the flash after a second or two and the camera would shut down after the batteries had been freshly charged! This happens sometimes with the Powerex 2700's if I take a couple pictures in a row and the voltage is 1.3V or below, but never happened with either two pairs of Energizer 2500's or either pair of Sony 2500's I used to use. They didn't die until their voltage was well below 1.2V.

The capacity of the 2700's and Imedions always checked out, I used to have one of those nice LaCrosse chargers.

 

[ampdude]

I find this surprosing. The Powerex 2700s are the best cells I own. Consistently showing capacities over 2700 mAh with a low self-discharge rate for standard LSD cells. They're the only non-LSD cells I would buy at this point. My Sanyo 2500 cells were terrible, the Powerex 2500s in the same league as the 2700s in my book.

Yea... well I thought the same thing as well when I first got them. Of course I only charged them in the LaCrosse and looked at the capacity numbers, then used them in an LED light.

It was after I started putting them into service with my camera I noticed their weak spot.

 

[Ziemas]

I've had no problems at all with Powerex 2700 cells in the cold. Just today I used two for a combined 45 minutes in -5c while biking with a LD2. I'll use the same batteries tomorrow as well, without recharging them. I've done this many times.

OP, have you contacted Maha? They offer a long warranty on their cells.

 

[ampdude]

I've never had any NIMH problems related to cold either.

 

[Yucca Patrol]

I just finished a refresh/analyze cycle on a set of 4 2700mAh Powerex batteries that have been charged many times and used/abused in my caving headlamps for the past 2 years. Each of them had a measured capacity greater than 2600mAh.

After 2 years, I'm impressed that they maintain greater than 96% of their rated capacity.

 

[Burgess]

But, how do they hold up, after a couple weeks off the charger ?


_

 

[Ziemas]

But, how do they hold up, after a couple weeks off the charger ?


_

Just fine. I use some in my shortwave radio, and they can sit in there for months.

I also did a simple test where I charged a Maha 2700 and an Eneloop, waited a month, and discharged them. The Maha came out well ahead of the Eneloop.

 

[etc]

I've had no problems at all with Powerex 2700 cells in the cold. Just today I used two for a combined 45 minutes in -5c while biking with a LD2. I'll use the same batteries tomorrow as well, without recharging them. I've done this many times.

OP, have you contacted Maha? They offer a long warranty on their cells.

maybe it's something particular to the GPS?

It did however fire upon Eneloops.