View Full Version : Rechargeable Batteries

10th Oct 2011, 05:03
I decided to "go green" and save some money by buying a load of rechargeable batteries. I got AA's AAA's and 9v's I got a charger and the idea was that the remotes, Wii handset, clocks, etc would never need me to buy batteries for them again. The problem is that the charged batteries only last 5 minutes. A normal battery will run the clock for 2 years a rechargeable one for 3 months. Normal batteries will run the Wii handset for about 12 hours the rechargeable ones for about 2 etc etc.
Has anybody else found this problem with rechargeable batteries?

10th Oct 2011, 05:07
Rechargeables last a lot longer in my Wii handsets, I'm guessing you maybe didn't look at the mAh rating?

10th Oct 2011, 05:27
More likely they are rated at very high mah ratings but made in China.

very shoddy batteries come from there

10th Oct 2011, 05:39
The self-discharge rate in rechargables can be very high indeed, so in general they're not suitable for things like remotes, where a normal battery might last years.

However Sanyo (now Panasonic) Eneloop rechargables have an extremely low self-discharge rate. So low, in fact, they're sold pre-charged. They'll work fine in remotes. Standard AA Eneloops are 1900 mAh, but since there's little self-discharge you can rely on that capacity being available when you get around to using the cell. I have a Sanyo charging station for 20 cells, and I have around 80 cells, half of which are in use at any one time.

2 hours in a Wii remote? That sounds bad for any battery.

10th Oct 2011, 06:08
Regular 1.5v batteries AA or AAA seem to have a fully charged voltage of about 1.6volts but re-chargeable batteries only get to 1.4volts. Is this also a factor ?
and why ?

(I'm a bit like Thurber's Aunt when it comes to electricity - she thought that if you didn't screw a light bulb into the ceiling socket in the middle of the room, then all the electricity would pour out over the carpet, and be wasted. )

10th Oct 2011, 06:11
These are great I use them in my camera.

AA 2400mAh Ni-MH - 4 Pack - Jaycar Electronics (http://www.jaycar.com.au/productView.asp?ID=SB1735&keywords=sb1735&form=KEYWORD)

Very low self discharge

10th Oct 2011, 06:19
My local Guru reckons Sanyo are the best re-chargeables.

10th Oct 2011, 07:01
Probably, pound for pound, the best investment I ever made! We used to get through about 30 batteries a week (no rude comments please!) with Wii's and remotes, and all the other assorted crap of a woman and a teenage son in the house.

10th Oct 2011, 07:42
I am using Energiser's I would have thought they would be good, I'll have a go at the Sanyo's if I can find them.

10th Oct 2011, 07:53
I bought a charger that will recharge standard alkalines, they last fine in the doorbell, clocks and remotes, have to replace them after maybe 10/12 charging cycles (or if I run them right down), but that's years in those applications. For applications requiring more frequent charging (camera, travel razor etc.) I use NimH cells, get the highest mAH rating I can find, no problems with these - but I always charge them up before going away or to an event where I will be using them.


Flap 5
10th Oct 2011, 08:13
I am using Energiser's I would have thought they would be good, I'll have a go at the Sanyo's if I can find them.

The Energizer bunny has a lot to answer for! Adverts are intended to make a company's product look good. How good they actually are is quite another thing. Although Energizer batteries are generally good the advert is rather insistent!

For Sanyo Eneloops look here:


Flap 5
10th Oct 2011, 08:23
By the way you say you 'decided to go green'. Really? I do dislike it when people assume they are 'green' by doing things which they have no knowledge about. Again you are going on what you have heard from the 'media' and other people.

I do wish people would understand what 'going green' really is. A Toyota Prius is supposed to be 'green' and yet it's batteries are incredibly environmentally unfriendly and a small diesel car would have better fuel consumption. A little knowledge ...

tony draper
10th Oct 2011, 08:46
My wireless keyboard and mouse eat batteries installed a new set in me mouse that went flat in 24 hours,seems to be poor quality control in some battery manufacturors.
Talking of normal type batteries there not the rechargable ones

10th Oct 2011, 08:50
I do dislike it when people assume they are 'green' by doing things which they have no knowledge about. Again you are going on what you have heard from the 'media' and other people.

Fair comment, Flap 5, but could you explain how buying a battery charger and 4 batteries which can be recharged and will probably last for a couple of years is not better for the environment than buying perhaps 50 sets of disposable batteries over the same period?

I accept what you say in respect of 'green cars' and a lot of the other rubbish which is foisted upon us by the tree huggers. I was very annoyed when my o/h bought what I can only call a worm shit device for compost. It's made of heavy plastic and came from Australia by air. It now sits outside and the resulting fluid is poured onto the tomato plants and herbs.

The worst offenders in daily life, my pet hates, are bottled water and air conditioning. The former has been banned in some parts of Australia, and even China has introduced some controls on the over usage of a/c.

10th Oct 2011, 10:30
I am using Energiser's I would have thought they would be good, I'll have a go at the Sanyo's if I can find them.

What you need to look out for are "industrial use" batteries. You can use them in the same gadgets you use the shop-bought batteries in, but because they've got a different chemical makeup, they tend to last longer.

10th Oct 2011, 10:42
Lithium-ion batteries as used in laptops phones etc perform well with high capacities and liitle self discharge , I have a combi drill with a lithium pack exellent .
But the cell voltage at 3.6v or so means they cant be made as substitutes ffor AA cells .
NiMh in my opinion dont perform as well as the old NiCd cells as apart from a few specialist types they have high self discharge rates .

Ancient Observer
10th Oct 2011, 12:43
tesco cheapo re-chargeables working fine in the ancient household. Used in remotes, and torches, and no problems so far. (Touch wood)

10th Oct 2011, 13:49
Saw device "recharging mats" on sale in Paris last week. Trouble is none of my devices have an inductive charging system built in (unlike the electric Rolls Royce Phantom).

10th Oct 2011, 18:05
The mobile phone, camera and the mp3 player however all have similiar sized batteries and chargers. Why can't they be interchangable? They are all from the same manufacturer.

Hear Hear. I have recently decided to aim for all the stuff I travel with to take the same batteries, so I need less spares and only one charger, and to not even take the charger for short trips. Have managed to get the still camera and travel shaver on to the same type, next one to replace is the aging video camera but I fear I will struggle to get a phone that takes the same ones, but then I only switch it on for a few minutes every couple of days when away so a full charge will last a fortnight's holiday.


10th Oct 2011, 18:28
That's what i think too . http://www.imgquick.com/images/43.gif

10th Oct 2011, 22:16
Leaving NiMHs in the charger seems to boil off the electrolyte. A lot of the four cell AA/AAA chargers don't seem to switch to a trickle charge so they cook their contents.

Li-Ions are great. My cordless Dremel has always had useful power in it, even months after the last charge. Expensive tool but worth every penny.

10th Oct 2011, 23:07
Question for the rechargeable battery experts. Can you get a thermal runaway while charging a modern rechargeable pattery?

Airborne Aircrew
10th Oct 2011, 23:38
It is, according to my neighbor who is very good at this stuff, to utterly flatten the battery between uses. So much so that many high end chargers have a "Discharge" setting that you use to completely flatten the battery before the charge cycle begins. It's all to do with the crystal size within the battery. If you don't flatten it completely the crystals remain large and discharge more quickly.

Cheap rechargers don't cycle the batteries so you need to do it yourself.

11th Oct 2011, 00:04
AA, LOL....
For my ancient VHS video camera battery pack I had a separate (quite cheap) 'discharger' gadget. Put the not quite empty battery in, and an hour or so later it would blink and bleep, to tell you the battery was now really 'empty'.

Looking at the 'doculentation', etc. it seems this is useful and works well for NiCads - it seems that 'topping up' partly discharged NiCads is not a good idea - while NiMHs can be 'topped up' without too many adverse effects.


Loose rivets
11th Oct 2011, 00:21
Rechargable batteries seem to go flat quickly because their nominal voltage is so low in the first place. 1.2v is typical. Most kit's processors will report a low voltage within moments of being used.

A more modern technology produced a 1.5v cell, but it really didn't stand the test of multi-use.

In the last few years, there have been some spectacular batteries, I used a couple on one of those mega-torches/flashlights one can get nowadays. Shine it on the river on me late night walks in Texas, and all the turtles dive in and swim away.

Vast power, and with a performance graph in the manual. The fall-off time is very, very short.

11th Oct 2011, 01:56
Just 15 minutes ago I had delivered the NZ Consumer Magazine, the equivalent of the UK "Which".

They've 'done' re-chargeable batteries this month.

Their top picks are
2-Sanyo Eneloop
3-Sony Multi Use
5-Energiser Recharge

Duracell, Varta and Panasonic were not thought very highly of.

You pays your money and you takes your pick.

11th Oct 2011, 02:12
There's a very good chance that numbers 1 to 3 are the same battery, and a 50% chance of number 4 being the same.