Rechargeable batteries what's that all about?

[TheAnimus]

i use relatively cheap recharable AA batteries, they start out at about 2500mAh, but after 18-24 months use in things like tourches, radios, camera they're normally down to about 1500mAh, this is sadly too common after about 50 charges.

with things like CR123As i've found that all too often the power tails right off, very quickly, so for my airsoft tourch (which is designed to be blinding) i tend to use dry cells. But as i normally get through about 3 sets a year, its hardly a problem. They do work fine in the lasers thou.

[TooNice]

Alkaline batteries have low price going for them and they last years in low drain devices (e.g. remote controls). Eneloop batteries hold their charges very well, and while they are not suitable for high drain devices, they are ideal for those low drain devices. The problem is, they aren't cheap - how many alkaline batteries can you buy for the 10 quids or so it cost to buy a pack of eneloop batteries?

Still, I've used rechargeable for quite a while now. The main reason being, there is no easy way to dispose of them in a clean manner. Unlike in Switzerland (at least years ago) where many supermarkets (or at least Co-op as I remember) would take those dead alkaline batteries, I found that there are fewer places in the UK that takes them. And it's kinda drilled into me that throwing dead batteries in the rubbish bin is a very, very naughty thing to do.

And rechargeable batteries have been gotten better. I went back to alkaline the first time I tried rechargeable because I found them crap for high drain devices. But if you pick a good rechargeable batteries aren't half bad these days. They may not be your Duracell M3 or whatever is the top alkaline battery these days, but they are good enough. The problem though is that there are still plenty of crappy rechargeable batteries, and going simply by the mAh is inadequate to pick them out. I believe that Maha, Sanyo (including non eneloop) and Energizer make some of the more consistently good rechargeable. I am using Sanyo (2700 mAH) at the moment and can vouch for them (over Uniross and Boot I previously used) though it's been a while since I have checked battery 'enthusiast' forums (yes there are such places - you'll find people debating the virtues of £50 chargers over less expensive).

[TheAnimus]

surely all chargers are simply a current source?

[TooNice]

I've don't use enough AA powered device to really care, but apparently some chargers are more 'gentle' than others and capable of getting the battery nearer to full capacity than cheap chargers like the travel charger I am using. Apparently 'lesser chargers' often overcharge (damage the battery which result in a decreased lifespan), or stop charging at sooner (I forgot the number but it may be something like 80&#37.

[shadowmaster]

I use these

usbcell - revolutionary rechargeable usb battery that can charge from any USB port

Quite useful if you have more spare usb ports then plug sockets

[Butcher]

In very high current drain devices (like digicams) rechargeables last longer than alkaline batteries - my old cam would kill duracells in 20 mins, but a set of cheap rechargeables would last about an hour (pro tip: never buy a digicam that uses AAAs).

Also, if you do use alkalines in something like a camera don't forget they'll still have a good bit of charge left over afterwards (high current drain doesn't fully flatten them), so you can stick them in a TV remote or something and get months more life out of them.

[kalniel]

Steven, you are a plonker

surely all chargers are simply a current source?

Yep, it's the 'how long to keep supplying the current' question, as well as the amount to provide, that chargers vary in.

The main problem with rechargable batteries is that there are so many different capacities now - most cheap chargers are designed to charge the batteries that come with them in about 8 hours so they literally provide a set current and then turn it off after a timer. The current is never so large as to damage the battery if you try and charge an already charged battery, but it won't fully charge a higher capacity battery. This caught me out when I bought some 2700mA ones and thought they were naff.. they weren't, I was just only ever charging them to about 1/3rd capacity

So instead I got a 1 pound battery charger that doesn't have a timer - it has a table on the back of the package which tells you how long to leave them in before turning off 26 hours later and I have batteries that seem to last forever - certainly far longer than non-rechargables.

[Sinizter]

I've never used rechargeable batteries because the only things in my house that uses batteries (other than the ones in cameras and phones) are remote controls. Need to replace the batteries once in 4-8 months depending on the particular remote and how much use it sees. Chances are I would probably have lost the recharger by the time I would need it. Or that the batteries would run out precisely when I need it and I would end up buying normal alkaline ones to tide me over while recharging them.

I do try to buy everything possible - cameras, console controllers, etc with rechargeables the first time around, but buying normal AA/AAA rechargeable batteries is not really for me.

[Lee H]

I have loads of 2300 mAH AA sized rechargeables I purchased from work that I originally bought to use with the S9500 but now they've migrated through the house to things like the wii-mote and even my DVD remote

[Mike Fishcake]

Beware of some of the cheap AA charger kits - I've seen some that come with 1300mAh batteries, which is absolute crap. You need to get decent branded 2500mAh or above really. Can't remember what brand mine are, but they last chuffin' ages in my Wii remotes and camera.

[Kumagoro]

I have eneloop batts and would recommend them. They have been vastly more
useful than normal nimh ones. The charger they come with (well the ones in Japan)
are switch mode and very small.

[mikerr]

Yeah basically, with eneloop or hybrio (same thing) rechargeables you can charge them up and leave them in a drawer ready to use.

Most normal rechargebles drain inside a month (or less!) whether you use them or not !

[TheAnimus]

Yep, it's the 'how long to keep supplying the current' question, as well as the amount to provide, that chargers vary in.

Hmm, i thought they would just mesure the voltage drop accross the battery, to determine when its fully charged, then switch off, like you do with a laptop.

[chicken]

I think the important thing is to decide what you need batteries for and put the appropriate ones in the appropriate devices.

As Rave said, Torches/Cameras/Mp3 Players you'd be silly not to use rechargables. NiMH (go for the 2500mAh rated or higher).

Remotes and other minimally-used, low-drain devices use the eneloop rechargeable batteries if you really want to be environmentally concious, or just use standard non-rechargable alkalines since you'll only be replacing them every couple of years.

I'm currently using 2500mAh Energiser batteries in my camera and they last for ages, but I've been eyeing up this site for getting some more... Just a bit unsure whether the cheapness/performance trade off is going to be worthwhile...

[kalniel]

Hmm, i thought they would just mesure the voltage drop accross the battery, to determine when its fully charged, then switch off, like you do with a laptop.

More expensive ones do, but none of the ones I own do that.

I'm currently using 2500mAh Energiser batteries in my camera and they last for ages, but I've been eyeing up this site for getting some more... Just a bit unsure whether the cheapness/performance trade off is going to be worthwhile...

I just worry they can't agree on their prices

'UK RRP £13.99'
'7dayshop Price £10.99'
'NORMALLY £4.29 '

'whilst we are charging you JUST £4.49 for a pack of rechargeable's '
'and all that by spending just £3.99'

[Whalefish]

Good article on rechargeables here