Showing results for 
Search instead for 
Did you mean: 

AA/AAA Battery charger.

Community Veteran
Posts: 8,583
Thanks: 954
Fixes: 9
Registered: ‎02-08-2007

AA/AAA Battery charger.

Have used a Uniross quick battery charger for a number of years which was replaced a couple of week ago with a Energiser battery charger, both took around the same time to charge the batteries (approx 90 minutes) Using the Energiser the batteries get very hot when compared to the Uniross to the point where I would be concerned leaving the charger unattended.
During charging batteries are clearly going to get warm but these are almost too hot to hold in your hand......... anyone else had this when using a charger. ?
Community Veteran
Posts: 6,773
Thanks: 258
Fixes: 21
Registered: ‎16-02-2009

Re: AA/AAA Battery charger.

Fast charge = HOT battery.
If you want cool batteries use a slow/overnight charger.
If it is "intelligent" then they will cool down after reaching charged state.
Community Veteran
Posts: 14,420
Thanks: 721
Fixes: 12
Registered: ‎01-08-2007

Re: AA/AAA Battery charger.

Personally I would trust uniross far more than energizer. Energizer are the big brand, big publicity company (also formerly known as Ever Ready) yet Uniross just "get on with it".
I've noticed over the years that companys who spend a lot on brand marketing don't always have a quality product like those who stay quiet and actually make something decent.
I need a new signature... i'm bored of the old one!
Aspiring Pro
Posts: 1,119
Thanks: 30
Fixes: 5
Registered: ‎04-11-2011

Re: AA/AAA Battery charger.

Fast charging also reduces battery life considerably, so should only be used sparingly.
That's RPM to you!!
Rising Star
Posts: 401
Thanks: 1
Fixes: 1
Registered: ‎31-07-2007

Re: AA/AAA Battery charger.

I have a Uniross charger and the batteries also get very very hot. They have also not lasted very long either.
I think an overnight trickle charge as @RPMozley suggests is the only way to preserve battery life.
Posts: 1,398
Thanks: 6
Registered: ‎17-11-2012

Re: AA/AAA Battery charger.

Used a Uniross rapid charger for a very long time. Most of the time the batteries remain cool. It is only occasionally that one may get hot.
That all said, I no longer get to use my Uniross batteries in my camera because they 'die' almost immediately, despite being fully charged.
Seasoned Pro
Posts: 6,170
Thanks: 268
Fixes: 3
Registered: ‎19-06-2011

Re: AA/AAA Battery charger.

I have been interested in Batteries (and Torches) for many years, and have quite a bit of experience of batteries, Alkaline and Rechargeable & Chargers.
At work in the past, and domestically too.
All portable broadcast equipment relies heavily on Batteries, and the care & maintenance of the same, in particular, charging.
I use 3 makes of Rechargeable Battery chargers, all have the same basic spec...
6-Level Charge Protection

Delta V/0 Delta V cut off

Over Temperature Protection (55oC)

Timer Control Protection (4.5 Hours)

Reverse Polarity Protection

Over Current and Short Circuit Protection

Defective and Non-rechargeable battery detection

Low Current Leakage Minimizes loss of capacity and maintains charging of battery by Controlling Current Leakage

Trickle Charge to Maintain Battery Charge

Worldwide Voltage 100-240V
Being: In order of preference
1) Sony BCG-34HD4            5 hours to charge 2,700mah AA  Ni-MH
2) Fujicell 808 LCD             2.5 hours to charge 2,700mah AA  Ni-MH
3) Contour  CHIBRUAA4      5 hours to charge 2,700mah AA  Ni-MH
Two of each, and they will all charge 1,2,3 or 4 batteries individually at the same time.
Using these chargers, in particular 1) and 2), I have been using & recharging the same Eneloop and Hybrio AA and AAA LSD batteries since November 2007 ( six years) initial bulk purchase, with no noticeable, nor measurable loss of capacity.
They have travelled the world with me, and are ideal for use in my Digital Cameras.
3) is a recent addition. ( Contour Batteries are re-badged Eneloops)
I rotate between my stock of 64 AA LSD's and 40 AAA LSD's with around 4 x 6 AA and 4 x 5 AAA not in use at any one time.
All in individual 4 pack storage cases, with charge dates on a label on the front. Using the oldest charged first.
And tested with a digital battery tester, under load.

BTW, for my chargers anyway, I did some 24 hours tests, and Nimh left in unplugged charger does not discharge batteries at all.
My older Ni-MH batteries, pre LSD, and charged with a variety of chargers, mostly timed charges, usually lasted a couple of years at the most.
So Battery & Charger technology has improved battery life and dependability.
I've just bought a load more Eneloops, more as a backup than anything else, though I don't expect to be using them any time soon !!

Chargers 2) and 3) shown below...