Rechargable battery life

  Terry Brown 12:19 PM 20 Mar 11

How long shoud a rechargable battery last.

I have some for about 2 years now and they have had a fair amount of use, but now they do not seem to charge properly.

I have tried a different charger.

I have been told that sometimes, if you completly discharge the battery, and re-charge it helps.

Can you recommend a good battery(rechargable)- currenty using Jessops 2100.

Any Advice.

  oresome 15:18 PM 20 Mar 11

Rule of thumb used to be around 1000 charges if treated correctly.

I've not had that success with AA batteries for the camera. They seem to last around 2 years with a charge every month.

Although I think the voltage is quite critical for the camera and rechargeables start at a disadvantage compared with say alkaline primary cells. 1.2v compared to 1.5v.

  alB 15:24 PM 20 Mar 11

I had similar problem with Uniross batteries, didn't hold the charge for long bought a set of Duracell click here really pleased with them ...alB

  Terry Brown 16:26 PM 20 Mar 11


In veiw of what you said, I have just read the small print on the charger unit and it says '2 x 2.8v), which means each battery gets 1.4v not 1.5v.

To get a car battery running at 12v, the charge is usually 14v -15v at start, dropping to 12v when charged.

By that reckoning, the inital charge shoud be about 1.7v dropping to 1.5v when charged.

or is my maths wrong?.

  oresome 16:44 PM 20 Mar 11

The terminal voltage of rechargeables is nearer 1.2v.

Rechargeables require a constant current charger as the voltage remains fairly constant over the charge/discharge cycle, unlike a lead acid car battery, where the voltage rises and the charge current reduces as charging progresses.

  hastelloy 09:50 AM 21 Mar 11

I have loads of rechargeables which don't retain their charge at all well. I have recently started to use click here - so far, so good.

  dms_05 10:52 AM 21 Mar 11

marvin42 is quite correct the sanyo eneloop series (other brands are available) use a different cathode/anode configuration and retains up to 80% of the original charge after a year. So they come already charged. I have a few AA and AAA size and can confirm they do retain their charge very well.

  Graham. 10:19 AM 28 Mar 11

I've been using click here for 5 years. They last for ever in my camera. The charger is click here

  dms_05 12:12 PM 28 Mar 11

Ni-Mh batteries loose about 10% of their charge in the first day then up to 1% everyday (say 5% a week). So they retain a usable charge for a relatively short time and so aren't suitable for low power use like clocks. The eneloop technology retains the overall charge density of a Ni-Mh but introduces a much better charge retention and can be used in low power uses.

  oresome 13:11 PM 28 Mar 11

"Ni-Mh batteries loose about 10% of their charge in the first day then up to 1% everyday (say 5% a week)."

It does explain why the camera always requires charging when I come to use it and the spare batteries have little life in them.

Same with the electric screwdriver.......always dead when I come to want to use it.

Not really suitable for equipment that's used infrequently.

  Terry Brown 17:32 PM 28 Mar 11

Thanks for all the info, I did not realise there was so much difference in batteries, but it certainly answers the question of why my rechargables are rarely usuable.



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