E5450 extended battery (R0TMP) discharge problem - meter jumps from 25-40% to 7% but works.

Replaced original battery (died after 20 days of warranty expire date!) by R0TMP - 62 Wh extended one. NB detected it fine, as genuine Dell and so on. It lasts for 6 hours or even more, but behavior is wrong.

Discharge goes smooth from 100 to 40% but after this jumps to 7% in a second. Then - rapidly to 0%. Any action on low charge is switched of soo it continue to work for about 1-2 hours at 0% indication - this means that battery has the charge but system detects it wrong.

I did everything I found reasonable:

- remove battery and AC and hold power button for 40 secs.

- remove battery, power on AC, uninstall battery driver in device manager, install battery and power on again.

- did 3 cycles of 100% -> dead.

What I observe that first discharge was 45%->7% step. Second was 35%-7% step and third today was 25%-7%. 

It looks like the system step-by-step understanding the battery, and may be after 3 more cycles it will work properly. But, from other hand, it seems that NB "remember" it's old battery and thus decide each time that 100-35% discharge must empty the battery. So may be I need just "move some switch" somewhere I didn't found yet, to explain to the system that battery now 62 Wh?