It has been some years since I've had an excuse to purchase a battery charger. Since then rechargeable batteries have invaded the supermarkets, and battery chargers have become much more mainstream. I was looking forward to discovering what reasonably-priced advanced chargers were available. I found lots of great options, some from very surprising outlets.Supermarkets and general electrical shops seemed to stock mostly dumb chargers. These require batteries to be charged in pairs, and turn off automatically after a set amount of time. This can lead to an empty battery not being fully charged, or an almost full battery being overcharged. As an example of a dumb charger, the Energizer Value Charger is sold at Tesco for £15. A step up from this is the Energizer Intelligent Charger, £20 at Tesco (though cheaper if you go searching online). This latter model does some monitoring of the battery and an indication of how long charging will take, though Amazon customer reviews are critical of the inconsistent charging results, and reviews on Energizer's own site at quite negative. Again, it only charges batteries in pairs.
If you move on from the supermarket then a whole world of online battery chargers is available. There are so many options that you only way to sort through them is to rely on crowd consensus, and pick a reliable forum. The main contenders were:
Ikea Ladda battery charger: £10
Cheap, simple, functional well-reviewed charger. It costs less than the Energizer dumb and slightly less dumb chargers, but is a proper intelligent charger. It charges until a battery is full rather than for a set time, and can charge from 1 to 4 batteries. Not many people have reported buying it, possibly because battery charging fanatics want even more functionality, and non-fanatics probably stick with a known battery brand, rather than the rather unexpected Ikea version.
Nitecore Intellicharge i4 V2: £16
Cheap, but possibly a bit more intelligent than the Ikea Ladda. Of the chargers I've looked at this is the only one which does LiIon in addition to NiCad and NiMH. Recharging aficionados will be put off by the lack of a display, other than some coloured LEDs indicating status.
BC-700 Alpha Power 9 in 1 Intelligent Battery Charger (Amazon): £22
We've finally entered the price range of intelligent chargers with LCD displays, giving a plethora of information about your cells. This Technoline model is highly regarded, and aside from charging can also do testing and refreshing of batteries. The charging level is adjustable per battery, so you can do a delicate slow charge to preserve your battery's health, or a fast charge if you're in a hurry.
Technoline BL-700 Intelligent Battery Charger: £32
For an extra £10 you can get the UK specific model of the aforementioned BC-700. The only difference is that you get a UK-only charger, whereas the BC-700 comes with a build-your-own charger, into which you can insert a Euro or a UK plug. This results in not a wobbly travel adaptor, but a totally normal UK charger. There is no reason to pay extra for the UK model. In fact, the BC-700 is more useful as it's ready to be taken to Europe.
AccuPower LCD Fast Charger IQ328: £25
This seems to be as functional as the BC-700, but has fewer reviews and more questions.
Maha MH-C9000 Wizard One £46
The ultimate charger is the MH-C9000. If your life depends on charging batteries, you'd probably want to go with this one. It offers a few more features than the BC/BL-700, but nothing of interest to me, and certainly not for double the price.
Of these, I'd recommend the Ikea Ladda for most people. For an intelligent charger to be cheaper than most dumb chargers it's an easy choice to make. If you go through a lot of rechargeable batteries then the ability to refresh dying ones would lead me to suggest the BC-700 as being a good value option. Finally, if you don't go through too many batteries, but you really want to see the nitty-gritty of voltages and current charging levels then the BC-700 again will serve you well. That's the reason I bought the BC-700, and it has already proved illuminating.