I've been holding my dear n900 for a few years now, and after a 3rd battery replacement (2012) i decided to buy another one (battery).

as soon as the battery arrived, i switched off my phone and i inserted the new battery. I tried switching it on, but it wouldn't start, so i put my computer micro-usb into it; after a bright orange flash from the led it went silent. i also tried with the wall charger, but to no avail. The old battery and chargers work fine, so it's not a hardware problem. I think i have a flat battery (search the forum for a while), but there seems to be no way to handle it easily. Any suggestions?

Have you tried to bend the small contact connectors on the battery? I had an issue where a battery was causing the phone to shut off and this was the problem. You'll need a fairly small watch type size screw driver for most control, but anything that has the strength and size should be fine. Just be sure not to short the battery by touch 2 connectors at the same time, which is hard to do since they are recessed. And of course you are reponsable for breaking your battery, phone, or shocking /fire. have fun & good luck x

This would appear to be common for the new "Nokia". Nokia themselves informed me that I should only by their products directly from Amazon.com (not another seller through Amazon, but Amazon themselves through Amazon) before Microsoft took over the company. I purchased a new BL-5J a few weeks ago from Amazon.com and it would not take a charge (Amazon exchanged it) and another BL-5J came with a Nokia Lumia 521 I purchased from T-Mobile days later and that BL-5J also would not take a charge (returned to T-Mobile). If the battery is new and will not take a charge return it immediately to the retailer which sold it to you. Do not wait to do so as they may not take it back if you wait to long.
All three BL-5J batteries I purchaced from Amazon before the Microsoft takeover (1320mAH with holographic decals) worked without issue (and now serve as my emergency backup batteries).

Hi There,

I have just bought a new BL-5j battery with the changed capacity (1430 mAh). Will it work with my phone?

Now I am charging it through USB cable, as I don't have a proper wall charger. I has Nokia sign on it but no holographic sticker.

new Nokia batteries do not have that sticker if the battery was manufactured in 2013 or later.

I recently bought a battery which is pretending to have 1600mAh capacity. It is sold by Amazon itself, not market place:
http://www.amazon.de/dp/B002HCTZCI
It was not at all charging or recognized by N900 and I had to bend the connectors at the battery a bit (like xman suggested in its post from 2014). Since then it is working stable, with OK energy lasting. I think, it doesnt notably last longer than a 1300mAh one ...

So this battery has my recommendations to other N900 users ...
Thanks to "newer" Nokia Lumia 520/521 mobile phones it is at least possible to buy real BL-5J batteries nowadays, without holographic thingie though.

Side note: If you order from Germany, you can save shipping cost by additionally shopping a cheap book (the more boring the better) and cancel this item when the battery is delivered.
Use this link for an ordered list of cheap (and boring) books:
http://www.amazon.de/s/rh=n:52044011...price-asc-rank
The price is secondary, more interesting is that amazon doesnt have it in stock ...

Cheers, Ulle

It is a crazy situation, I am waiting for drfrostdk's next round of battery tests. It is good money to spend vs my wasting money on three different brand batteries so far which then dropped off like they had aged for three years on the shelf.
http://talk.maemo.org/showthread.php?t=65568
I recently used an akku polarcell vs an akku-king and it has not lasted 6months without dropping below 50% capacity(in a double cell configuration, no direct soldering burn to the battery).
Oh for the old and great Scuds we all admined, so great and so cheap.

I recently bought a "Master Instruments" replacement BL-5J from Battery World here in Australia. Capacity is listed on the label as 1300mAh, the "last measured discharge" shown by bq27200.sh is listed as 1484mAh and I bet if I let it go through another learning cycle, it will go even higher.