I just bought some new Duracell Rechargeable Accu AA 4 pack batteries for use with my Uniross CXH2 charger.

It's been suggested that I should replace my aging charger too.
Is there any truth in this as I didn't think the actual chargers needed replacing.

If you use it right then there is no problem at all with it.
There are better chargers out there that sort of do more and cope with both the uninformed user and a bad battery better.

But minimal truth.

Cheers Alan.

I suspected as much. Most likely the trainee sales assistant eager to make another sale.

Lucky for you it was a trainee!

Depending on the batteries and the charger, then it may well be a very good idea to replace the charger.

A quick googleage suggests the Uniross CXH2 is ancient (about ten years old or so) and has a switched NiCd / NiMH setting. That says two things to me-- one- it is does not detect how well charged your batteries are and instead relies on a fixed charge time for either type, and two, given how much higher capacity NiMH cells are these days, you are going to have to charge them two or three times in it to have a chance of it fully charging them.

Bin that charger as it is totally obsolete and replace it with a modern one with microprocessor controlled charging which monitors the cell voltage and detects when each individual cell is fully charged, and charges them all in an hour or two (with status indicators for each cell so you can see how things are gong). You can get a charger like that in Maplins for around £15 (with 4 AA cells included for free).

If you stick with your old Uniross charger, you are asking for a lot of tedious back-to-back charging sessions for each full use of the batteries, plus you have no way of knowing how well charged each battery is (it probably charges them in pairs, rather than as individual cells).

This is what I bought, and it works very well indeed with all my AA and AAA NiMH and NiCd cells (except one AA cell which it said was unusable and I have since confirmed on my multimeter was shortcircuited internally)
http://www.maplin.co.uk/Module.aspx?ModuleNo=394201

Hi Gaz,

Thanks for your input. You're right, I did purchase the charger many years ago and I was using the Uniross batteries that came with the charger up until recently when it became obvious that the batteries weren't holding charge anymore.

I charged the Duracells yesterday and it only took about 5 hours, which seemed a little bit quick to me. I'm not convinced they fully charged.

I had a look at the charger on the Maplin link you provided. I think I may well purchase this charger in the morning based on your positive comments.

If that is the first time you have charged then they were maybe already 50% charged.
It does show that you also have 'charge detect' on yours.

Older is not always better though the Maplin one is a very good buy.

Depends, if its got separate charge circuits for each battery and doesn't charge in pairs like cheap junk it might be ok. Does it vary in charge time depending on how drained the batteries are?
Thats the indicator, if it does, its fine.
Honestly i don't care that much about babying batteries, but if you do there are plenty of high end chargers like mahas and lacross and such. I just use a 15 minute duracell most of the time, even if theoretically halved the life span of my batteries its a couple cents per charge.

Even most mid priced stuff charges in pairs and is a nuisance.

The Maplins one looks similar in quality to the Tronic £13 6 cell one at LIDL.

Both good buys with the normal going rate for quality ones being £30+

Yeah, I've actually got one of the LIDL ones. Very good, charges each battery individually etc.

Bought mine when I needed to do 3 at a time.
The 6 capacity was very apt too.

However an over drained battery sometimes won't charge so I have to either warm it or put it in a cheap charger for a while first.
The conditioning feature sounds useful

And there was me a bit concerned about a charger which can do NiMH cells in an hour and a bit, not so much the less charge cycles bit, more the exploding batteries bit

That Maplin one I bought has four individual charge circuits for the cells, and displays the charge level on a LCD display with a three bar level indicator for each cell. I've tested it with a mix of drained, recently fully charged, and partly discharged cells and after a minute or so it showed the dead one as charging with one bar flashing, the full one had already stopped charging with all three bars on, and the partly used one had two bars steady with the top one flashing and it finished charging long before the fully discharged one did.

I'm pretty confident therefore that it knows what it is doing, and for £15 including 4 hybrid NiMH AA cells seems like pretty good value to me, which is why I bought it after my previous charger packed in.

A pleasant surprise was the LCD display is lit for the duration of it charging any cell so you can easily see how its doing in any lighting conditions, as well as whether it has finished or not from a distance (as the light goes out then). It does have a discharge function as well which might be handy for NiCd cells but I've never used those for decades.

One thing some people might dislike is it is a two-part unit-- it has a mains-adapter plug which you plug into the charger part. The upside of that I suppose is it reduces the temperature of the actual charger, plus it allows it to be used with the included car cigarette-lighter thing instead if you want to use it in a car (I don't have a car).

If this sounds a bit like a sales pitch, I should point out that I have no affiliation in any way with Maplins or any battery/charger company, other than as a satisfied customer (so far, I've only had it a couple of weeks). Anyway it is available for another week at £15 before something else is in the Maplins sale instead.

http://www.batteryuniversity.com/

Well chargers that work in an hour tend not to have any actual cooling..which is an issue. I've found with my 15 minute duracell the fan cools the battery below the point of many fast chargers, so i'm fine with it.

There are many fancy chargers that will condition or refresh older batteries and such stuff, but its a luxury, as unless you have professional needs the extra cost of the charger isn't going to pay for itself in extra battery cycles it "saves" for probably decades lol. If you divide the cost of a battery cycle use by its purchase price, over hundreds of uses its next to nothing. but well in any case nice stuff is nice. I just chose to go with convenience of speed over long life as possible is all, the 15 minute chargers aren't all that cheap either. I just like the "last minute" practicality of it all.

That's a good point; the cells in my one and a bit hour charger sometimes get quite warm at the end of the charge cycle. Never actually so warm as to be hot enough for me to be concerned about them, but enough for it to be noticeable (compared with the rest of the charge cycle when they remain at room temperature).

I've always preferred to have at least one set of AAA and AA cells fully charged and ready for use at all times, and the increasing availability and similar price of the so-called hybried NiMH cells makes this an ever more viable option (when they only hold their charge two or three months, having a set in storage doesn't always work, but if they're gonna hold most of their charge for over a year, it's a different story).

A 15 min charge time is nice, but no charge time at all is better if these hybrid rechargeables I've got actually live up to their hype (I'm not convinced they will, but I'll see if they're any good when I actually use them).

After reporting capacity the Tronic one conditions by first discharging some and/or using a safer 10 minute impulse charge. All depending on how the battery is.

Of course all irrelevant when things are fine anyway.
Hybrids are great compared to higher capacity batteries when you charge less than once per month. Thus fine in remote controls too.