Rechargeable Batteries - how much money DO they save?

Radshire

I have a dilemma and I'm sure someone can point me in the right direction.

Christmas is coming and this means toys for my boy from the whole family - all of which will inevitably require batteries. In order to keep these toys running I can see that I have three options.

1. Buy normal, good quality batteries
2. Buy really cheap batteries from poundland etc.
3. Invest in rechargeable batteries.

As a moneysaver, what should I do and how much can I expect to save?

Option 1 is more expensive than option 2, but in the long term may be cheaper. Option 3 is the most expensive up front, but does it really pay off when you include the fact that rechargeables don't last as long as good quality batteries, have a finite number of charge cycles, and cost money to charge.

If I go with option 3, I'm going the whole hog. I'll buy enough batteries to replace all the other types of batteries in the house.

NeverInDebt

False economy buying cheap batteries for high powered stuff, fine for remote controls/torches

I tend to always have some on charge so if a battery runs out I have instant supply. If you have high usage devices like cameras then go for highest ones NiMH 2700+ mAh. NiMH batteries do loose there power over time so now you can get ones that dont loose as much like Sanyo Eneloop these do tend to be slightly lower powered though around 2000 mAh

http://www.eneloop.info/products/batteries.html

Tyler_Du

http://www.frequencycast.co.uk/rechargeablebatteries.html

Leif

Buy Low Self Discharge NiNH cells. These keep ~80% of their charge over a year. Non LSD NiMH cells lose about 0.5% charge per day. And LSD cells are cheaper. I buy from 7DayShop, although delivery can be very slow. Eneloop are very good LSD cells. Just because a cell has a higher capacity does not mean you actually get that much extra power. They wear out more quickly, and they self discharge, so unless you use them soon after charging, the higher capacity is meaningless. LSD cells are much more robust. (There are technical reasons. Basically high capacity cells have a thinner membrane between the two key chemicals, and it wears out more quickly.)

grizzly1911

Leif wrote: »

Buy Low Self Discharge NiNH cells. These keep ~80% of their charge over a year. Non LSD NiMH cells lose about 0.5% charge per day. And LSD cells are cheaper. I buy from 7DayShop, although delivery can be very slow. Eneloop are very good LSD cells. Just because a cell has a higher capacity does not mean you actually get that much extra power. They wear out more quickly, and they self discharge, so unless you use them soon after charging, the higher capacity is meaningless. LSD cells are much more robust. (There are technical reasons. Basically high capacity cells have a thinner membrane between the two key chemicals, and it wears out more quickly.)

I agree -GP Recyko batteries aren't much different in price to "Duracell" types.

Uniross and Maxell do their own variants too. Checkout Amazon for good range and prices.

I replaced my old charger with an Energizer CHEUF universal charger (£14 on Amazon v £20 in shops) works well and charges (4 in Pairs) quickly (AA/AAA 2/3hours C/D probably twice as long). Some of the very fast chargers can damage batteries I have read. This one also tells you when they are bad too.

http://www.amazon.co.uk/Energize-Charger-Universal-629874-ENGRHUNI/dp/B000Y8572E/ref=sr_1_2?ie=UTF8&qid=1319974092&sr=8-2

When we had kids toys to worry about I used to have a surplus set or two so you could rotate batteries to make sure you already have some charged up. Nothing worse than powered toys with no power. Maybe mark the set 1,2,3 etc. may help?

kabayiri

I'd agree with the comments above, but also add a note about cheap batteries.

The cheaper batteries are the ones I find more likely to 'leak' and corrode the terminals inside the appliance. This is more likely in a low use appliance where you might not change the battery for a long time, and therefore not check.

Throwing away broken appliances is also not very MSE.

foomanchu

There is really no downside to NiMH rechargables.

Their capacity is higher than Alkalines (which are usually about 1800mah I think though the manufacturers don't like to talk about it!) so they generally last longer even with slightly higher self discharge rates.

I keep a pot of pre charged AAs & AAAs ready for use. I keep the Alkalines I don’t use in case of emergency.

Some cells I’ve had for years & still going strong though I would like a better charger that perhaps gives me the battery condition so I know when to finally retire them.

Are there less heavy metals etc in them too?

Leif

grizzly1911 wrote: »

I
I replaced my old charger with an Energizer CHEUF universal charger (£14 on Amazon v £20 in shops) works well and charges (4 in Pairs) quickly (AA/AAA 2/3hours C/D probably twice as long). Some of the very fast chargers can damage batteries I have read.

Fast chargers do damage batteries. 2 hour chargers are fine. The best charge cells individually.

And another advantage. When you have two ordinary cells in series, one can reverse charge the other which causes leakage. NiMH cells are unlikely to leak.

Ben84

I'm not a huge battery user, but I bought a charger and rechargeable batteries a few years ago as I realised the pay back was still pretty fast and there are other benefits too.

An important point is buying good rechargeable batteries as there is a lot of difference between the good and the bad ones. I always buy the eneloop ones now (often they're half price on amazon) because they don't self discharge rapidly, I've found I can charge them and put them in the draw until I need them, even if it's a year later. They also last a long time in use in most appliances because their voltage drops slowly as they discharge. High mAh batteries look appealing, but usually the appliance stops long before the battery is flat because the voltage drops off fast and quickly isn't sufficient to power it any more. Digital cameras nearly always suffer from this. So, despite their lower mAh rating, my eneloop batteries power my appliances for longer. I used to often use two sets of regular rechargeable batteries a day in my camera, now one set can last three days.

Anyway, I paid about £6 for a set of four AA, which isn't a lot more than the good disposable ones. The cost to charge them is basically insignificant, a fraction of a penny I expect. The charger was the major cost, about £20, so within about four sets of disposable batteries avoided it paid for itself.

So, good financial benefits (even low battery users can break even within a year I expect) and there are other benefits too. It's convenient, I don't have to remember to buy batteries any more. I usually have some in the draw charged and ready to use, but I can also charge them in about one hour if needed. Saves going to the shops, possibly very helpful if the shops are closed. They're also much better for the environment.

santer_2

Some test results here

http://e-group.uk.net/forum/showthread.php?t=6331

http://forums.dpreview.com/forums/read.asp?forum=1023&message=24756026

http://www.users.on.net/~mhains/Tables/swiff/eneloop-v-hybrio.swf

TimBuckTeeth

Rechargeable batteries are ideal for high drain items such as motorised toys, torches and digital cameras.
They are not ideal for low drain items that last many months from one set of batteries such as clocks and remote controls, due to the self-discharge characteristic mentioned above and the payback period would be years.

Never buy cheap batteries they don't last long and leak ruining the item they are in. Only buy good quality alkaline batteries, beware of cheap branded ones as there are some fake duracells about.

Get some good NiMh batteries for the high drain items, it will be well worth it, but don't change everything in the house, keep alkaline for the clocks etc.

When choosing a charger get a good fast charger. The slow chargers are poorer quality and don't cut off at the end of charge which can reduce the life of the batteries. Choose one with independent charging channels, chargers that will only charge in pairs, 2 or 4 at a time will not give each battery the optimum charge and are not much good if you need to charge 3 batteries.

If you want a really good charger which tells you how much capacity the battery has, I would recommend this one, it is not cheap but will charge the batteries optimally and the capacity tester is useful, unfortunately it is for AAA and AA size batteries only.
http://www.amazon.co.uk/dp/B003S4JQS2