I just purchased an 12-cell 8800mAh battery to replace the 6-cell 4400mAh unit that came with my Compaq C700. After fitting the new battery, I'm seeing exactly the same ACPI info as I saw with my old battery:
present: yes
design capacity: 4752 mWh
last full capacity: 4752 mWh
battery technology: rechargeable
design voltage: 10800 mV
design capacity warning: 475 mWh
design capacity low: 256 mWh
cycle count: 0
capacity granularity 1: 264 mWh
capacity granularity 2: 3780 mWh
model number: Primary
serial number:
battery type: Lion
OEM info: Hewlett-Packard
Is it possible that the ACPI info is in error, or is this 12-cell battery really no more capacious than my old six-cell?
Followup: In use, the battery is performing the way I'd expect a 12-cell to perform, but it is definitely returning the wrong info to ACPI. It looks like what's happened is that the manufacturer has directly copied the data being reported by the genuine HP batteries.