New battery - strange behaviour

[garmcqui]

My old 48Wh 4-cell battery wasn't lasting long enough (1.5hrs), so I purchased a 86.5Wh 9-cell battery a few days ago.

However I noticed the Windows low battery indicator came on quicker with the new battery (after about 1hr)!!!

So I downloaded BatteryMon and looked at the battery characteristics:



This pic shows the battery fully charged, with the AC adapter connected. I don't understand why the full-charge capacity is so much lower than the design capacity and the current capacity.

As soon as I unplug the AC adapter however, the current capacity jumps down to:



And within 1 minute it's chaged to this (notice the 57W discharge rate!):



It continues to drain until it reaches 6% (after about 1hr), but the weird thing is it will stay at 6% for well over another hour!

What's going on? With the old battery the discharge rate is only 21W!

Thanks,

Gareth

[David (PassMark)]

Battery packs are semi intelligent. They have some chips in them that talk to the charging circuit in the laptop to report status & characteristics.
My guess is that the new battery pack isn't 100% compatible with the charging circuit. The result is incorrect status information.

There are some good details of how the battery system works in this document.