I repair old mac's and I have never been able to get the level upto 100% I use third party batteries, and like the other user commented, I would not concern myself to much. For future reference and as it might help others, you can try CS batteries as I do, I get mine from Ebay but have been bitten once or twice with delays as sellers ship from Asia, there is one UK company Best Battery that I now use as they are in the UK.