rechargeable batteries: are they worth it?

[Fred]

Hi,

Before Christmas I bought lots of toys that needed batteries. I waited and waited for Lidl to do an offer on rechargeables but could not wait forever so I bought a pack of 40 alkaline AAs from CPC for about £7. They also sell 40 AAA for about the same price. I think that works out about 17p per battery.

When Lidl sold their NiMH batteries a few weeks later, I think they were £2.99 for 4, which I think makes them about five times more expensive than the CPC alkalines, or in other words, I would have to use them five times to get payback. That's not including the electricity or charger to recharge them.

I just wonder whether it is worth the hassle of recharging batteries when alkalines seem so cheap and convenient. CPC also sell zinc carbon batteries for even less. I know alkaline is for more heavy duty loads but I wonder if Zinc carbon would be enough to flash a few lights and make a few sounds on children's toys. If so, they would seem to be a better choice than NiHM.

What does the panel think? TIA

[Huge]

IME, no. I gave up with rechargeables for most things some years ago.

[Martin Brown]

In a fair world you should get a few more AAAs for constant price pack. I have found the Poundland Kodak ones about the cheapest cheerful ones - last time I looked £1 for 12 special offer or 8p each.

The electricity to charge them is noise in the general scheme of things

- a 2Ah AA 1.4v cell will recharge about 80 times from 1kWhr of mains.

Depends how disciplined you are about using them and keeping them as sets and charged ready to use. The old NiMH that lost their charge in a matter of weeks if unused were pretty dire but the latest low self discharge types are pretty easy to use for 10-50 recharges so long as you don't have someone throwing them out when they run out of charge.

Some last longer than that. And the odd one dies prematurely. I use a pretty large selection of rechargeables up to and including D cells.

It is worth using sacrificial cells in places where they may be subject to serious abuse - like children leaving torches on for days. Being at zero volts into a dead short for extended periods will kill them.

Generally it is a win to use rechargables when you can, but you always need a few classical cells in reserve for emergencies.

[Dave Liquorice]

You should get several hundred "uses" from a set of rechargeables...

The decent charger will be just under =A320 from Lidl/Aldi.

Only you can judge that. A lot depends on how often you need to change the batteries. There is a nighlight here that gets through a set of 3 AAA's every three days or so. So that's =A37.99 every 40 days at your co= sts or around =A372/year against =A323 for a set of NiMH AAA's and charger. = The amount of electricty consumed is well less than a tenner (assuming 10W

24/7 (which it won't be) =3D 87kWHrs @ 10p/kWHr =3D =A38.70) so call the= rechargeable route =A330 first year after that it's =A38.70/year for let= s say 3 years (121 * 3 =3D 363 cycles).

Alkaline 3 year cost =3D 72 * 3 =3D =A3216.00 Rechargeable 3 year cost =3D 20 + 3 + (8.7 *3) =3D =A349.10

[Apellation Controlee]

Aren't rechargeable batteries lower rated voltage than expendables?

[Dave Plowman (News)]

I use re-chargables in a couple of mouses and keyboards and have recharged them more times than I can remember. Alkalines do last longer, but I reckon I'm quids in. I keep spares ready recharged to hand.

[Martin Brown]

The no load terminal voltage is lower, but the internal resistance is also lower so that under a heavy load it more or less balances out.

There are a few devices - my old Kodak DC-120 was one of them that are tetchy about being used on rechargeable cells as they sense the battery pack terminal voltage under no load and refuse to switch on!

Using rechargables in cheap flash guns you have to be a little bit careful as their low internal resistance means that the current draw can be enough to burn out the step-up transformer if you take a long run of flash shots one after another.

[Broadback]

I've certainly given up on re-chargeables, not worth the hassle IMHO, and adding the re-charger price not that much of a saving.

[meow2222]

that's the marketing line. Really they're not well suited to heavy loads, i= t reduces their capacity heavily, and its heavy loads where nimh win most.

sure, the old zinc carbons work and are cheap. But they're the worst option= in terms of capacity per cost. And they leak routinely.

Rechargeables: reasonably good AA ones now give similar capacity to alkalin= e. At =A31 a cell lasting say 400 charges that's 0.25p per charge. Alkaline= AAs at 17p each are thus 68x the cost.

Where capacity isnt so important, poundland do 1/3 the capacity rechargeabl= es for half the price.

NT

[Dave Plowman (News)]

The saving here is considerable. Provided I don't charge my time for changing them. Other thing is I don't suddenly run out of batteries.

[djc]

For things that are regularly used I think rechargeables are best. The

4AAs in my radio seem to last a couple of weeks between charges and have been in use for over a year. For my small camera the two AA cells were fine when recharged after daily use but not suitable to keep in a camera that may not b used for weeks. Similarly for the GPS, I used rechargebles when out walking but put alkalines back in when it is stored.

[Brian Gaff]

Well I use rechargeable and the latest ones seem a lot less prone to self discharge than the ones of only 18 months ago. I've got a set here that has already been rough 18 times, so it really depends on the use and the current drain.

Brian

[Adam Funk]

That's pretty much my experience too. I find by trial & error that NiMH rechargeables don't work well in a few things (e.g., the Wii remotes can play up but the battery indicators on the screen don't indicate they're low), but really not many.

[John Rumm]

Probably worth noting that the cheap alkaline batts at CPC are usually GP branded. I usually find these to be pretty poor compared to real batteries.

[Bob Eager]

Last week I got 24 AA cells from CPC for about £7.70. That's about as low as I'd go - they were Energizer ones. Duracell Procell are around the same price. Any cheaper and they're GP, as you say, and not nearly as good.

[Adam Funk]

TBH, I've been buying Maplin's own brand of AAs & AAAs when they're on sale, with what I feel are reasonable results; but as a result of previous discussion here I'm going to keep an eye out for low-self-discharge ones at Aldi/Lidl & try them next.

[whisky-dave]

I'd suggest you look at the toys themselves unless they have an option or a= setting for recharbles then it's unlikely recharables would be a good idea= , some cheap toys might not work for very long due to the lower voltage 1.2= V compared teh 1.5V alkaline and that can make quite a differnce with 4 cel= ls or more. I've had cheap LED torches that work well with Alkaline batteri= es but quickly fail when useing recharbles as those =A31 shop torches use t= he relatively high intenal resistance of alkaline cells to current limit. W= hen usoing recharables they get rather warm and tend to stop woring after a= n hour or so and it's not the batteries that 'die' the LEDS do .

If a product is designed for recharbles I tend to think and from expeienece= that they are a good idea and well worth while, but putting rechargable ba= tteries in equipemtn not designed for them isn't a good idea.

I have a fujifinepix camera HCS10 that takes both types but you need to set= that on the camera, not tried setting the wrong ones yet for obvious reaso= ns :-)

[chris French]

In message , "Dave Plowman (News)" writes

Yeah, I mostly use rechargables nowadays, I've gradually built up a stock of mostly low self discharge ones, and so find I use them in most things as they last a decent amount of time even in things like TV remotes. A decent stock, and having ones that don't lose charge very quickly when stored charged makes it all easy.

[John Rumm]

They had some Philips branded ones that I ordered on special last week. I got 48 AAAs for £7.90 + VAT

[tony sayer]

I bought a box of 40 from Toolstation I'll let you know how they last!..

There're 25 p each. I've also used them for button cells CR2000 type for computers and lead acid's for alarm panels and the like...

Doesn't seem to be much they don't do these days;!...