Rechargable Batteries?

[magicbeatle]

Hi,
I recently bought a digital camera, and a Uniross Sprint (1hr) rechargable battery kit. At first it worked exellently, the batteries lasting a long time. However, now I charge the batteries (Sometimes overnight) yet they completely lose power after just a few minutes in the camera. The batteries had only been recharged about 10 times before this started happening. I was under the impression that they should recharge a few thousand times. Any idea why this is happening? Is it the batteries, or could it be the camera? It did take a bit of a knock recently. However, apart from the battery power, it works fine.

[anotheoldgit]

Only way to find out is to buy another set of batteries, and this will prove if the battery charger is working ok or your batteries are faulty.

[Buenchico]

This sounds like the dreaded 'memory effect'.

With the older type of rechargeable batteries (nickel cadmium), it was widely known that it was necessary to fully discharge the batteries before recharging them. Otherwise, the 'memory effect' could come into play. For example, if you had a set of batteries which would give you 200 pictures and you used them until they were 'dead', recharging them would make them fit for another 200 pictures. However if you only took 50 pictures and recharged them, the batteries might only be fit to provide a further 50 shots or so. After just a few times of giving 'top up' charges, the batteries would be virtually useless. (Good quality battery chargers were designed to totally discharge the batteries before commencing the charging process, to overcome this problem).

When the newer rechargeable batteries (nickel metal hydride) were introduced, they were more expensive than the older type but they sold well largely upon claims that they didn't display the memory effect. So I bought some and, assured by the claims that I could top them up before they were fully discharged, always topped them up after just a few pictures. Very soon, I experienced exactly the same problems which you're having, i.e. the batteries wouldn't hold a charge.

Concerned about this, I e-mailed the manufacturers (Duracell). The reply stated that, while the effect is not always as great, nickel metal hydride batteries also suffer from the memory effect and should only be charged after, or close to, exhaustion. (Alternatively, of course, a battery charger which first discharges the batteries could be used).

Unfortunately, once batteries have acquired their 'memory', it seems that there's little that can be done to bring them back to full use. You'll need to buy some new rechargeable cells and then ensure that you don't recharge them until they're nearly, or fully, exhausted.

Chris

[tyler durden]

if you bought them recently i'd take them back to the shop & ask them to replace them. But yeah, try a pair of non rechargable batteries to make sure your camera doesnt have an electrical fault. It may be working normally but if you dropped it, a component inside could be sapping energy without you knowing.
Also i wouldnt advise leaving the batteries on overnight charge -even if the charger has an automatic cut out.

[magicbeatle]

Thanks everyone. I didnt know that you needed to fully drain their energy before re-charging. I have been re-charging when they still had life in them. Sometimes,if I fully charge the batteries and leave them somewhere for a few hours before putting them in the camera, they will be totally dead. I will buy some new ones and try them. Ive lost the charger instructions, do I have to drain new batteries before a first time charge, or can I charge them straight away?

[Buenchico]

Thanks for your response.

New rechargeable batteries are supplied uncharged. You need to charge them before you can use them. Batteries need to be charged and fully discharged several times before they'll hold their maximum charge.

Chris

[ACtheTROLL]

Be careful here

You don't say what type of batteries you have ....
I assume not older batteries (NiCad) which do indeed benefit from full discharge but should not be used with a fast charger unless it has a NiCad setting - or you have a flak jacket (the current is far too high for old batteries)
to reset the memory ... fully discharge then put in fridge for a month or so (or just bin them!)

Your charger comes with 4x2500 NiMH - so I assume that's what you are using.

The newer high power NiMH claim not to develop memory
but should be almost totally discharged before recharging (bulb still glowing faintly - not dead)

The fast chargers are very useful ... but they knock hell out of the battery ..... I use a standard switched overnight charger most of the time and only use the quickie when I have to. Normally batteries will fail early ... or not at all (but will start to decline after about 800 charges)

This sounds like this is a take 'em back to the shop scenario.

A useful gizmo is a battery tester .... (cheaper than new batteries) - and that way you don't have to charge them unnecessarily (it's probable that only one of the batteries has failed)

Li-ion .... benefit from being discharged to about 25% before recharging to 55-65% of total (this gives max life - but is difficult to keep up to (they also explode when shot!?).

[magicbeatle]

Hi everyone,
Thanks again. I use 4x2700 mah, Ni-MH Uniross Batteries.