Battery Tests, Homemade 3000mAh XL Battery & Q&A (POST #1) - New Layout

[pichlo]

Originally Posted by mike727

Any ideas what this means, any difference?

That's just how they filled in the form. The two batteries look identical to me.

[biketool]

Since the current Polarcells I bought are ending up sub 900mA/h (2-pack is at 1800) after 90 days I am going to try OEM Nokia BL-5Js and hopefully get around 2400-2600mA/h out of a double pack. As far as I am concerned the Polarcells for sale are either old or fake as evidenced by comments on this thread....
And still no Scuds around for sale, what a great battery, a lost magic similar to the brew used for the N900.

[handaxe]

Agreed that it is sad. I wonder if Polar cell simply rebrand batteries made elsewhere and have changed their original supplier? It is quite something to go from pack leader to rip-off. Not even 1350 mAh but 900. Sheesh !

[biketool]

To be fair they were at around 1300mA/h new but that dropped away after three or four discharges and 900 is after three months.
I suspect they are the same cells which have sat on a shelf degrading internally as time passed.

[handaxe]

Originally Posted by biketool

To be fair they were at around 1300mA/h new but that dropped away after three or four discharges and 900 is after three months.
I suspect they are the same cells which have sat on a shelf degrading internally as time passed.

Perhaps so. Still rip-off territory. My old Polarcell is calibrated still at ca. 12/1300MAh after 2.5 years.

[biketool]

Now there is the problem of finding what I think is currently the best battery. A genuine OEM BL-5J form Nokia. Everyone claims to sell a genuine Nokia battery, but where can one be safely purchased at a reasonable price. I even suspect the phone shops, as they have every incentive to sell fakes with the Nokia sticker.

[dr_frost_dk]

Since im still using my N900 maybe i should make a new Thread about 2015 Battery tests.

EDIT: a quick ebay search shows many options still even in 2015, so should be enough to test.

[biketool]

Originally Posted by dr_frost_dk

Since im still using my N900 maybe i should make a new Thread about 2015 Battery tests.

This is a very important thread for everyone using a N900 as a data or video device, especially those who do not have the Mugen cover Double-cell mod. Contributing financially to the research means that we can all save quite a bit on batteries rather than buying an expensive series of duds. Maybe if everyone contributed the price of a battery, or contacted dr_frost_dk to had a cell in need of testing delivered to him for the new comparison chart. Remember contributing to a new battery comparison chart saves you money in the end.

[biketool]

I just callibrated my double Polarcell pack today, the 2x BL-5J pack is don to 980mA/h that is 490mA/h each on packs marked to be 1500mA/h each, that is after about six months of use.
I accept that there is no return to the amazing Scud, that technology is apparently lost to geek-kind but someone point me to a BL-5J battery which at least will keep a realistic 1000mA/h for a t least a year so I can build a double pack.

[jurop88]

Recently bought a new battery for my N900 since it's still my daily runner, the last good original BL-5J started having issues and my old Polarcell dropped to 980mA.
Battery is Patona from Amazon, last measured discharge = 1537mA (usual bq27k stuff). I got through one day with no recharges, a thing that made me very happy.
Let's see now for how much time the battery will keep this performance...