Rechargable batteries - How do they compare to standard ones?

NeilF

NeilF

NeilF

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So if you have a device which say uses a pair of AA batteries. If you put in your typical Duracell ones, or say a pair of 2800MAH rechargable ones. What will the difference be?

2800MAH rechargables are towards the top of AA rechargables, so how do they compare against regular AA (non-rechargables) in longevity etc?
 
i've some 2700mah AA rechargeables. they seem to be ok but wouldnt be as good as a new set of duracell.
i always tend to go with rechargeables because even if i dont get as long from a charge its usually cheaper than buying a dozens sets on new duracell
 
chipperhead said:
I bought some cheap 2500mah aa from ebay, they are terrible. If you do get rechargeable at least get decent ones.
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I've got some 2700mah Uniross ones, and looking at also getting some 2900mah Fujimax... Just interested on how these batteries are suppose to compare to 'proper' batteries though...
 
I find the main problem with recharageables is the discharge rate when they are not being used. Got some duracell rechargeables and they are absolutely terrible. Go flat in a few days just sitting on the desk!

Also got some ansmann ones and they are superb. Seem as good as normal batteries. Ansmann are the ones I would recommend without a doubt.
 
Keep in mind that rechargeable batteries are only putting out 1.2 volts compared to the 1.5 volts alkaline batteries do.

I have a set of Uniross 2500 mAh Ni-MH AAs and they work really well in things like digital cameras, comparable to a fresh set of alkaline batteries. If you are going with rechargeables then you need to buy a decent brand land get them from a reputable source, not eBay or Poundland. You also need a good charger for them, one that knows when to stop charging, Ni-CD and Ni-MH batteries charge differently so you need the correct charger or one that supports both types.

You can also get low self-discharge NiMH batteries which don't lose their charge as fast when not in use. They don't come in as higher capacities as normal rechargables but they are better for applications where the batteries sit unused for longer periods of time. One brand of these batteries is called Eneloop.
 
Drukk said:
I find the main problem with recharageables is the discharge rate when they are not being used. Got some duracell rechargeables and they are absolutely terrible. Go flat in a few days just sitting on the desk!

Also got some ansmann ones and they are superb. Seem as good as normal batteries. Ansmann are the ones I would recommend without a doubt.
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Read some details reviews of them so ordered some 2850 ones... Thanks!

Not cheap, but if it means I don't have to recharge them so often it'll be worth it...

They're mainly going to be used in things like Wii handsets.
 
RobH said:
Keep in mind that rechargeable batteries are only putting out 1.2 volts compared to the 1.5 volts alkaline batteries do.
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Yep, this can indeed be a problem. It really depends on what you'll be using them for.

RobH said:
I have a set of Uniross 2500 mAh Ni-MH AAs and they work really well in things like digital cameras, comparable to a fresh set of alkaline batteries. If you are going with rechargeables then you need to buy a decent brand land get them from a reputable source, not eBay or Poundland. You also need a good charger for them, one that knows when to stop charging, Ni-CD and Ni-MH batteries charge differently so you need the correct charger or one that supports both types.
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Absolutely. Buying non-branded rechargeables or chargers is a total waste, and will put you off them. Buy Uniross or Sanyo or something and you'll be fine.

RobH said:
You can also get low self-discharge NiMH batteries which don't lose their charge as fast when not in use. They don't come in as higher capacities as normal rechargables but they are better for applications where the batteries sit unused for longer periods of time. One brand of these batteries is called Eneloop.
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Eneloop is made by Sanyo, who invented the technology. It's said that theirs are the best, but I've no idea really. I have loads of Uniross Hybrio batteries which are their version of low self-discharge batteries and they're brilliant. They mainly get used in my digital camera and my Wii remotes and they work absolutely brilliantly.
 
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I ordered 8 3000 mAh GP rechargables of ebay

They are terrible. They don't seem to ever fully charge and they go dead very quick both just sitting and when in use.

The biggest thing you need to keep in mind when buying high power rechargables is the charger.

The average AA charger outputs 190 - 220 mA, this is fine for the lower power 2200 - 2500 batteries but no good for the higher power 2800 - 3200 type.

That may well be why mine don't charge very well as my charger is 220mA and really I need 290 - 300mA
 
Larkspeed,

Or just leave them charging for longer... With your charging rate you need to leave it going for at least 15 hours to get to full charge.
 
I have these Vapex 2900 mAh ones from ebay, I use them with an Energizer battery charter, I'm not sure if they're good or not, but I user 2 of em in a LED light and on full (180lumen) they last about 2 hours.
 
saitrix said:
Larkspeed,

Or just leave them charging for longer... With your charging rate you need to leave it going for at least 15 hours to get to full charge.
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tried that it makes no difference.

i think it's just because the charger does not have the grunt to push the top end of the power in.

i was surprised, as was already said, GP are usualy very good batteries, I have lots of stuff here that came supplied with GP's and they are all great.

Eventually I will get a more powerful charger but the 300mA ones are pretty pricey
 
Larkspeed said:
The average AA charger outputs 190 - 220 mA, this is fine for the lower power 2200 - 2500 batteries but no good for the higher power 2800 - 3200 type.

That may well be why mine don't charge very well as my charger is 220mA and really I need 290 - 300mA
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For a slow/overnight charging its supposed to be C/10 or less. So 10% of charge or less, it'll just take a little longer. Fast charging is a bit more complicated, iirc the NiMh batteries have to be discharged first to avoid damage. It all gets a bit involved.
Larkspeed said:
tried that it makes no difference.

i think it's just because the charger does not have the grunt to push the top end of the power in.
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You could trickle charge to full capacity, a few milliamps, just takes longer is all. The higher current rates could cause the battery to vent and damage the batteries memory.
 
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