Wiki: Are rechargeables worth it?

[Mark]

I guess low self discharge rechargeables would work in remotes but I still use alkalines.

The main application I have found alkalines better is camera flashguns.

[Mark]

--snip--

+1.

The smaller wii remotes (uses AAA batteries) are even worse.

[PeterC]

gradual self discharge.

The LSD (Eneloop etc.) last well enough in clocks (9 months so far) but the voltage can be a problem with some clocks. I have quite a few clocks around the place and some stop at 1.2 - 1.3V and those aren't suitable for NiMH. One goes down to about 0.9 - 0.95V and that will do the 9 months, then the voltage is too low. Most of the LED torches are OK on Eneloops; the incandescent torches are down a bit but, for most uses, it doesn't matter. The good point, especially with LED torches, is that there's life after 18 months withous use. Some alkaline cells, even with several years to the nominal date, die within weeks - think 99p. The Kodak ones from Pound shop seem to do well in tests but I've not used any yet.

[Java Jive]

Actually, my Canon Powershot S40 has its own model of rechargable, and my two've got so tired that now, even with a newly charged battery, the battery warning indicator comes on the moment I open the camera!

I have learnt from this never to buy another product of any type that doesn't accept standard battery sizes - cordless phone, cordless mouse, etc, first thing I checked.

[Mark]

You'll not find that many cameras now that take standard battery sizes.

[Tony Bryer]

My Canon Powershot A720is runs fine on rechargeable AA cells. Dozens of shots before I need to swap them.

[Mike Lane]

Tony Bryer wrote on Jan 29, 2013:

I use lithium non-rechargeables in my Canon Powershot. One pair gives me many hundreds of shots - or nearly a year usually. I suppose I could save a few pounds a year by using rechargeables at the cost of carrying around a lot of charging equipment. For me it just isn't worth it.

[David.WE.Roberts]

Possibly the calculation can be misleading. Another way to look at it is that after you have used nine sets of alkalines at 17p a battery you have more or less broken even with an equivalent set of rechargeables.

[Obviously you have to have quite a few battery devices - otherwise the cost of the charger will skew the results.]

If your device uses a set of batteries a month you are in pocket within a year.

If your device uses a set of batteries a year then it may well be obsolete and retired long before you get your money back.

Rechargeables can be moved from device to device (assuming your new device is compatible) but how long to the rechargeables last if only discharged/ charged over a long period?

I know the rechargeables on constant charge in devices such as DECT phone handsets curl up and die after a few years.

So the recharge cycle isn't the only factor to be used in calculations.

How long in years can a battery last before the structure starts to fail? This could be a lot shorter that the theoretical number of charge/ discharge cycles if the charge/discharge cycle is long.

Oh, and how long does your average battery charger last?

Another assumption - the cost of batteries stays stable over an extended period.

If non-rechargeables become cheaper then payback time is longer and vice versa.

So the initial comparison only really hold good where you are using a lot of batteries over a relatively short period - perhaps 1-2 years.

Cheers

Dave R

[meow2222]

Sounds like you'd like to do a 3 page calculation for us. It will inevitabl= y be filled with guesses as to future price changes, inflation, shelf life,= charger life, appliance obsolescence, and so on, making it no more valid. = And the conclusion will be the same, making it pointless.

FWIW a few years ago I still had batteries and charger from the 80s, which = got used on occasion. They're obsolete now that LSD NiMH have taken over.

NT

[Andrew Gabriel]

Haven't looked recently, but Canon did many of their models in two versions - regular AA batteries, and proprietry Li-ion. Specifically went for the AA version.

[meow2222]

Version 3 with a lot more stuff....

NT

Rechargeable battery

=3D=3DTypes=3D=3D ;[[NiCad]]=20 :Low capacity, slow charge rate and toxic cadmium. A typical AA Nicad gives= 0.45Ah from a 15hr charge. 1.2v per cell.

;[[NimH]] :AA NiMH typically 0.8Ah - 2.8Ah, charge rates from 5hrs to 15 minutes. 1.2= v. New NiMH are mostly low self discharge (LSD), older ones steadily discha= rged themselves. LSD NiMH are usually labelled as ready-charged, something = that's not practical with earlier NiMH.

;Rechargeable alkaline :A rechargeable variant of [[Alkaline battery|alkaline]]. Not in general us= e in UK, can be bought from abroad. They don't last as well as NiMh and NiC= d, and have short lives if deep discharged. They provide 1.4v per cell when= recharged, an advantage for appliances that don't play well with NiCd and = NiMH.

Wikipedia= article]

;[[Lead acid]] :Large, heavy, lowest cost per capacity. Mainly used in cars. Acid spills i= f tipped.

;[[Lead acid|Sealed lead acid]] :SLA are spillproof variants of [[lead acid]]s. Mainly used in alarms, golf= & mobility buggies etc.

;Lithium ion :Li-ion cells store more energy than the same size NiMH, and charge faster,= hence their main use in laptops. Correct charging is essential, else they = explode.

;NiFe :Historic forerunner of NiCd. Seldom seen, but one manufacturer of industri= al sized cells does exist. Extremely long lived, some made in the 1920s sti= ll work. Most can be rejuvenated by replacing the electrolyte. Initial cost= higher than lead acid, but lifetime far longer.

=3D=3DAre rechargeables worth it?=3D=3D Good AA rechargeables ones now give similar capacity to [[Alkaline battery|= alkaline]], around 2.8Ah. At =A31.50 a cell lasting 500 charges that's 0.3p= per charge. Alkaline AAs at 17p each are thus 56x the cost.

[[Zinc carbon]]s are much cheaper per battery, but give even less capacity = per cost.

The cost of the recharging [[electricity]] is trivial. A 2.5Ah 1.2v cell ho= lds 3 watthours, or 0.003 kWh. Allowing for inefficiencies, 0.005kWh costs =

0.005x13p =3D 0.065p. You can recharge 15 for a penny.

• Alkaline cost: 17p each

• Rechargeable cost plus electricity: 0.365p

Where capacity isn't so important, [[cheap]] rechargeables at half the pric= e typically give around 1/3 the capacity.

=3D=3DWhen they're not as good=3D=3D Discussion of the apps where alkaline are better is [https://groups.google.=com/forum/?fromgroups#!topic/uk.d-i-y/2-fEtNS-DAQ here]

=3D=3DCordless tools=3D=3D NiCd 1.3-2 Ah are most common. Energy capacity =3D voltage x Amphours. The = quality of nicads varies widely, affecting how long they last in trade use.

Li-ion powered tools cost more, and are less likely to come with more than = one battery pack. The advantage is faster recharging.

Supercapacitor powered tools are rarely seen. These can only run the tool f= or seconds, and recharge in a second or so every time the tool is put back = on the charging cradle. The number of charge cycles is not limited as batte= ry chemistries are.

=3D=3DBattery failure=3D=3D Cordless tool NiCd battery packs can be recelled, but its too often not wor= thwhile. Recelling with budget brands may be cheap, but how long they last = in non-diy use is another matter.

NiCd and NiMH cells that won't hold charge can in theory be zapped with a m= oment of high charge current to burn out the shorting dendrites and make th= em work, but zapped cells quickly re-short.

Li-ion cells have limited life even when not used. A li-ion battery that's = little used lasts longest if stored half charged in a [[freezer]], wrapped = to keep it dry. Defrost before use, eat before sell by.

A seldom seen option is to run a 12v - 18v tool on a lead acid battery on a= short lead. It does at least provide many times the battery capacity. Curr= ent draw is upto 20A or 30A, so the [[flex]] should be rated to at least 5A= (30A wire would only be needed for continuous operation.)

Lead acids can sometimes be repaired by replacing the electrolyte, but hand= ling toxic lead compounds and acid for the cost of a new battery isn't usua= lly worthwhile.

=3D=3DSee also=3D=3D [[Alkaline battery]] [[NiMH battery]]

[[Category:Batteries]]

[Windmill]

Are those Li-ion batteries replaceable? I assume that like laptop batteries, 'ages' isn't as long as I would expect to keep a camera.

[Windmill]

to gradual self discharge.

If need be, you can usually find a lower voltage but (if you wish) higher power bulb for a torch. Krypton or halogen.

[Windmill]

Bastards.

[John Williamson]

The camera makers are getting on to the computer timeframe for new!, improved! models. and I suspect that when the unique Li-whatever battery for that model dies of old age, they won't be selling that type any more. I've got a Panasonic camera that uses a battery that could have been used one the same as an older model. but no... It's *almost* the same size and fittings, but just different enough that I can't use the old one. Some makers are also fitting chips in their batteries so that you have to use genuine batteries, not pattern parts.

[Clive George]

Yup. You generally charge them outside the camera.

Spares are common as muck these days. And unlike a laptop, the camera lasts a long time between charges so the batteries don't die in the same way.

[Tony Bryer]

My thought process is the opposite: I like to be able to swap batteries at any time if the need arises.

[John Williamson]

Very few, if any, cameras have li-ion batteries that can't be swapped in the field. I always carry at least one charged spare with me.

[Nick Odell]

I'm much the same here. I deliberately choose equipment that will run off standard AA cells because on more than one occasion I've been away from a meaningful supply of electricity for recharging for a week or more. For domestic use and in civilised for'n parts I use my Poundland NiMh rechargeables but further afield I (usually)use alkaline. I've never found a village where I can't buy at least some sort of AA cell

- and yes, sometimes I've had to resort to zinc-carbon. But zinc carbon will work - even if only for 20-30 shots

Nick

[Clive George]

I used to think that, but getting a camera with a decent battery life changed it.

I do use the camera most days, so don't suffer from not knowing what state it's in.