If its not a peak-detect (sometimes refered to as delta peak) charger, then it'll be a dumb charger. It'll either undercharge the batteries, or overcharge them.

Also chargers that charge in pairs aren't ideal either as it can't monitor each individual battery. Plus its annoying if you want to just charge an odd number of cells or have accidentally mixed up charged cells with discharged ones.

Batteries allowed to overcharge will just get hot, and if left too longwill just vent its internals (not that messy, usually just leaves a bit of white residue on the positive terminal). Usually the battery still works, but it generally doesn't work as well afterwards (self discharges, usually).

NiMH rechargables

Procell = Duracell without the fancy packaging and silly power test gizmo, very good in my experience.

Have you tried the USBCELL batteries?
Bought some today from Morrisons, reduced from £5.99 to £1.48 for a pack of 2 AA.
They are NiMH rechargables that you charge up from any USB port.

And no need to buy a special charger!

http://www.thinkgeek.com/images/prod..._batteries.jpg
http://www.usbcell.com/documents/Moi...cy%20Award.JPG

Vapextech.

http://www.vapextech.co.uk/

Good quality high capacity cells, plus one seriously rapid charger (individual delta peak).

But make sure they are the ready-charged ones. As these can be left on the shelf with very little self-discharging.

Most normal run of the mill Ni-MH cells self discharge (and get worse as they get older or damaged via bad charging). Great if in constant use, but no good to be left on the shelf or in infrequently used/low current drain items.

Best to get boths type; high capacity for contantly used items that draw high current (portable radios, r/c cars, cameras, incandecent torches), and the ready charged types for lesser used items or items with lower current drain (remote controls, LED torches, backup/spare batteries etc).

A decent charger will shut itself down automatically as the voltage in the batteries increases. Should not be a problem.

Les

+1

Packs of 48 Kirkland AA and AAA Alkaline batteries. Been buying these for years, haven't found any as good any cheaper. The AA's are something like £7 or £8 per pack of 48.

Costco - packs of 36 AA Duracells are £7.99 :D

Another vote here for Sanyo Eneloop and similar; they really do stay charged much, much longer than regular NiMH batteries, and if you get through a lot of AAs I'd definitely recommend them.

They do need the correct type of charger, though.

Ah thats a really useful post. We use rechargeables at work and they never last. Will definately look at replacing with what you recommend above. :thumb:

Depends Les; The vast majority of "automatic" AA chargers just shut down via an automatic timer and then go to a constant trickle charge. That's fine for nicads as they are more tolerant of overcharging, but not so good for Ni-MH which will reduce their rated working capacity. The majority of fast chargers (i.e five hours or less) are just crude timer circuits; Five hours and they shut off regardless of if the battery is under charged or overcharged.

A Ni-MH cell to be be fully charged from flat needs about 120% of its current capacity rating. for example, a 1500mAH cell requires 1800mAh, which is 3.6 hours for a 0.5amp charger. Now say that was a 5 hour charger that just used an automatic timer? It would be overcharged by over an hour!

Now say if the same charger was used to charge a flat 2200mAh cell; That would need 2400mAh to be fully charged, which with teh same 0.5amp charger would take 5.3 hours. Problem is, the timer shuts off at 5 hours, so its undercharged by 17 minutes.

Also if the charger is disturbed mid-cycle (turned on and off, or a cell is removed/replaced) the timer reset.

The same issues rises with partially charged cells or partially charged ones that get mixed up with flat ones as nearly all of these chargers charge in even pairs. Causing the partially charged cells will get overcharged, even if a pair of cells came out the same device; one may have more charge than the other (because discharge rates varies between each individual cell). This is why chargers that charge cells in pairs can also ruin good cells.

Why the hell battery manufacturers brand/sell chargers that damage the very same cells they sell is beyond me. I only assume its so that they wear out quicker so consumer buys more batteries. :cuckoo:

if the charger doesn't say "delta peak" or "peak detect" anywhere....regardless of how much it cost; Bin it IMO (or calculate the charge time yourself and use a stop watch: http://www.greenbatteries.com/batterycalc.html ).

Might be worth looking at my post directly above this too, to make sure your charger is up to the job. :thumb: :cool:

In what way are you saying Ni-Cad are more tolerant of overcharging than NiMH? I'd always read the complete opposite. Ni-Cad suffered very badly from memory-effect but NiMH didn't, and the only down-side to NiMH was that that they discharged over time even without use.

Both have a memory-effect, though nicads are far worse.

The biggest issue of using either is that you rarely bring all the cells down to a completely discharged state.

Before you recharge each cell must be discharged, then recharged, not only do you get a better charge, but you remove the memory effect.

Nicads should be discharge down to 0.1v.
Nimhs should be discharged down to 0.9v

Charge systems are different to, nicads are generally pusle charge, whereas nimhs are linear charge, but both with some form of peak detection.

Memory effect is the result of improper discharge techniques. (actually that is an incorrect term, as it actually crystalisation of the cell's internal chemical structure, causing loss of capacity and internal shorting).

A nicads must be fully discharged before charging, otherwise they will slowely but surely start to degrade in capacity. Ni-MH you can recharge a part discharged cell with less issues (problem is with a timed charger, its likely to get overcharged).

This was a pain in the arse back in the days when RC cars used to use nicads: 7.2v RC cars had so much current drain, they couldn't fully depleat the battery properly before the reciever/speed controller shut down. So the battery packs had to be discharged and balanced using other means (I used to use a 5watt 12volt light bulb :) ).

Ali,

I remember the lightbulb ;)

Loads of balancers out there now, however there's only one the I know of that work with 'AA's & AAA's, thats the Novak Smart Tray

http://www.teamnovak.com/products/di...ray/index.html

Now the RC world has gone Lipo\Life :)

If you want even more capacity have a look at sanyo eneloop xx, they now have 2500mah and have been just released, just make sure you use an eneloop charger as they're designed for the cells.

Ten packs of IKEA alkaline AA batteries for just under £2 a pack I find are as good as anything else I have tried and better than Duracell. Mainly use them in camera flashes so constant drain. Obviously make sure you dispose of them responsibly in recycling battery bins! :)

Hiya I odered the eneloop batteries but where is the best place to get a suitable charger?

Thank you. :thumb:

I have this same problem aswell, the Mrs. vibrator eats AA batterys

I hate it when that happens, :(

Try buying one with 'D' cells instead.....;)

I'll second that. I use a lot for different things at work and duracell had a habbit of just not working when going flat. Most others kind of let you know there going flat. I use Phillips and for the cost per use I'll not be using duracell again. I think it works out for £0.42 for a pack of 4 via Mico

ikea 10 for £1, there nto the longest lasting, but compared to a £5 for a pack of 4 duracel they work out way cheaper.

they also do aaa

If its just AA or AAA you are charging, this is a pretty damn good charger: http://www.amazon.co.uk/Technoline-B...5026294&sr=8-1

It will also test and tell the true capacity of your old batteries (many cheap 2000+mAh batteries can't delivery anywhere near their rated capacity). Instructions are a bit naff though. But I'm sure you'll work it out. :D

Alternatively if you need to charge 9v, D or C type cells there is this: http://www.buyabattery.co.uk/ansmann...er-p-1563.html

Or this: http://www.buyabattery.co.uk/ansmann...ger-p-655.html

I have the older version of the powerline 5, which is ok, But I found it doesn't charge AAA cells very well as the contacts aren't in the right place (keep having wiggle them). So maybe the newer one has been improved.

I think this thread went flat and then got re-charged somehow. I blame Ali :D

dl

24 Energiser in Robert Dyas for £2.99

Sounds painful, and she still puts it near her growler? Bit of a masochist?