Like a lot of people are finding, their N900 battery can run down pretty fast, particularly when you've got it connected all the time to either wifi or 3G, you've got push email or various widgets pulling down info constantly. For me it's the same, so I bought myself another battery on the cheap on ebay. However, I didn't really use it because I could never be bothered to take out the old one, charge the new one, then take out the new one and charge the old one etc. Too much work...

So, I decided I needed a desktop charger and looked around for one. There were quite a lot on ebay, but really wasn't sure of the quality so instead when for this one from Mobile Fun. For £20. Yes, absolutely ridiculous I know, but I wanted something that worked and was willing to pay a bit extra for it.

When I got it, it was difficult to work out where that £20 actually went on the device. It is made of very light, cheap, glossy plastic, the sort of thing you'd expect to pay about £2-3 for on ebay (and in fact that does seem to be the case)

When I first opened the packet, I thought they'd sent me the wrong one because the space for the battery was much larger than the battery itself, which you can see from this picture.



Turns out not to be the case, the charger is designed for several different battery sizes and so you have to carefully align the battery points on the BL-5J with the prongs on the charger and make sure you don't move the charger or bump into it in any way otherwise it will come loose and stop charging. Pretty shoddy quality all round to be honest.

When charging, the frosted light at the front flashes a glowing blue and the blue becomes permanent when it is fully charged. Takes about 2-3 hours on average to fully charge a completely empty battery.

The charger comes with two ports for charging, one the standard charging jack on many Nokia phones and the other the micro USB port as on the N900 itself (mini-USB, micro-USB, can never remember the names?). This means you can use either an old Nokia charger or the USB cable for charging.



With the charger comes a cable with the standard jack on one end and a host USB on the other for sticking into the computer. This is the best aspect of this, whether at work or home or someone's house, you can always find a cable to stick into the charger.

As I said, for the price the quality is pretty poor, but I do actually like the fact that it's small and light and not as heavy as some other external chargers I've had for camera batteries. I've found it easy to slip into a top pocket along with an extra battery and when I'm at work and one battery dies, I can quickly replace it and start charging the old one.





Overall, it's not bad, it does the job it's supposed to but there's no way they can justify selling this for £20 and I'm sure you can find ones of equally low-rent quality on Ebay for much cheaper. However, on the plus side, it does alleviate my endless fear that one day I am going to yank out the USB port on the N900. I haven't had to touch the wall charger for days now, and I'm very happy about that.....

I got one of the 'cheap on ebay' ones plus a spare battery - connects to the mini nokia charger (not the USB one), also charges in about 2-3 hours. Mine fits battery exactly and feels of cheap quality also. Has a red light when charging and a green one when charged. Doesn't switch off when it's charged so I keep an eye on it. Been using this and the usb charger (generally overnight as I don't like using the device with the charger plugged in) and this has meant I now generally have no battery worries...

The difference between well-built and poorly-built chargers is that the poorly-built ones are outright dangerous in use, while the well-built ones charge the batteries properly.

Take a digital multimeter, set it to the DC Voltage 20V range (or 10V, or 5V range if it has one), and measure the battery voltage once the charge is done.
If it's more than 4.20V -> Danger
Next, you need to find a way to secure the test leads between the battery terminal and the prong on the charger (the other battery terminal should be connected directly to the battery charger). However, this time set the multimeter to the DC Amps 10A range (a 2A or 1A range would be better but they're rare on meters). If it shows anything except 0 when the charge is complete -> trickle charge, dangerous.
Oh and be careful with the meter, if you have the leads plugged into the 10A hole and you put the leads onto + and - of the battery you cause a short circuit, which is also dangerous.

That was made to fit a BP-4L. I have the same one, works fine with the BL-5J.

i saw that one too. a friend recommends to get that one, but im worst that being a sloth in removing batteries. i got one, but use it not as much, coz i have the dc-11 which is more useful to me.

yes i know it'll not fully charge a 1320mah battery, but that will give me enough time to find a wall outlet and fully charge my device, i dont need to remove the battery too

you mentioned about a cheap battery from e-bay. is it original? or does it work fine???

please advise, thanks