It's your standard Lenovo 9 cell. I got mine from komputech and it was in decent condition for the price I paid ($22). It has 344 cycles on it and holds around 56 Wh, I seem to able to get 4 - 5 hours out of it which I feel is pretty good for its condition. If I was really frugal with my settings and usage I could probably get 6 hours out of it. I recommend it, it was a very nice upgrade over the heavily used 6 cell I was using.
GENUINE Lenovo 90W 20V Power Adapter for Lenovo ThinkPad 92P1105 42T5000 - GOOD!