A faster charger for rechargeable batteries?

Forgive me if I've overlooked something while trying to shop around for this. But I haven't found a battery charger in the UK that recharges in as fast a time as the one I had in the US.

My US charger got the job done on 2500 mAh, AA batteries in as little as 15 minutes.

The UK one I'm using now, a borrowed one, takes all damn day and overnight too before there is a full charge indicated.

It's likely on older model, but when I've gone shopping even the new ones (at least the ones I've seen) boast "24 hours charger!" like that's a superfast time!

Is there no such thing in the UK as a charger that claims it does the job in at least an hour or less, like my US one did?

Any tips on the make, model, and the UK stores where you've seen or bought one would be great.

Just doing a bit of research, I've found a Sony charger on Amazon.co.uk that says it charges in 15 minutes (but it's pricey though - almost £50):



There are a few other chargers on there too, but the ones I looked at took anywhere from 4 to 18 hours (UniRoss is the main brand of those ones, I think)

Wow, thanks for that, ksand24.

Yikes, fifty quid for a 15 minute model? I'm not sure but I think my US fast charger only cost about $19.99 at Best Buy....WITH a set of batteries included...!

This is one thing I guess, where the UK price can't compare to the US price. I've found they often do match each other in relative value, but yikes, not this one.

Oh well, I'll bite the bullet and try to get hold of one of these -- I miss not having my batteries all set to go again before its a whole other date on the calendar......

That may not be the only one around - I just found one at Argos for £29 that says it charges in 1 hour (http://www.argos.co.uk/static/Product/partNumber/9802034/Trail/searchtext%3EBATTERY+CHARGER.htm) and another that says 90 minutes (http://www.argos.co.uk/static/Product/partNumber/9800287/Trail/searchtext%3EBATTERY+CHARGER.htm).

Here's a UniRoss one that does it in 15 minutes too (only about £35): http://www.argos.co.uk/static/Product/partNumber/9801097/Trail/searchtext%3EBATTERY+CHARGER.htm

Oh you've made my day! (And now I feel lazy for not having managed to find this stuff myself, lol!)

A million thanks for being so sweet as to take time to find this! 

Hiya!

I think Paul will know more...

I remember reading somewhere about these so called 'super quick' chargers. I think they acheive this by some sort of 'over charging' - i.e excite the internal chemicals at a higher level. The 15 minute thing I think scientifically is that in that 15 minutes, the process will charge the batteries to a 'percentage' of it's capacity level - the figure 80% springs to mind here.

Newer battery chemicals technology means they're better suited to this rapid charging system/effect - older battery technology doesn't handle it well at all. Even so, I think the trade off for 15 minutes 80% charge is the number of charge (re) cycles is reduced.

So, long term, you'd probably have to replace those batteries more often than a standard charged cycled battery.

Of course, pricing for 'identical' goods in the UK is substantially higher in the UK than the USA - for various reasons! - lets not get into that here just now!

Check out other discount retailers such as Ebuyer and Play.com etc - might have some units on offer....

Cheers! DtM! West London & Slough UK

The downside to faster charging is the higher risk of overcharging, which can damage the battery. To detect all conditions of overcharge demands great sophistication from the charging circuit and a cheap charger will eventually damage even the best quality cells. However, many so called intelligent chargers employ a combination of cut off systems, which should prevent overcharging in the vast majority of cases.

Thanks DennistheMenace and contrex; good, interesting info. Although, I have to say, I've had a great experience with the fast charger I used to have, and the batteries it came with -- they've been recharged many times and are still going strong since December 2006, which is coming on two and a half years now -- not bad I would say!

The charger I had was a good one, it was Energizer brand I think, and had a built in fan for cooling, automatic cutoff when the batteries were charged, and LED lights to show the status and progress. Had a regular mains plug and a car adaptor for charging on the go. Man it was a great one....the ex got it.    ....but I hung onto the batteries! 

I've been using some NiMH (nickel metal hydride) rechargeables from Maplins since about 2003 and they still seem to hold charge OK. I use a very basic slow charger that does them in about 5 hours.

Those fast chargers do indeed stress the cells rather more in terms of the temperature rise and the chemical effect it has.  Fast charging really requires much more sophistication to ensure the quick charge without risk of overheating than most of the cheap units provide.

For a long time there was a rule-of-thumb that for optimum life batteries should not be charged faster than the 10-hour rate, or a current exceeding 10% of the rated ampere-hour capacity (e.g. a 2500mAh cell should be charged at no more than 250mA and would thus need 10 hours for a full charge from "empty").   Modern NiCd and other cells are more robust and can handle higher rates of charge without detriment, but there's still a need for careful control at such extremely fast rates.

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