I finally made some progress on reading out data using the “smart battery” interface on laptop battery packs. I’ve succeeded in pulling a number of useful numerical values from three different MacBook Pro batteries from two different manufacturers and one Acer battery pack. I have, so far, failed to get anything out of a different model of Acer pack, an ASUS pack, and an HP pack, but I have some ideas about what to try next. I also have to do more work to make sense of a few of the values I’m getting, and figure out how to read out string data, and figure out if I can get at voltages for individual parallel banks of cells.

In the meantime, here is what I got out of an old Mac battery:

Design Capacity (mAh): 5800

Design Voltage: 10800

Manufacture Date: 15400

Cycle Count: 531

Voltage: 12.23

Full Charge Capacity (mAh): 3073

Remaining Capacity (mAh): 2812

Relative Charge PCT: 92

Absolute Charge: 48

Temp: 31.85

Current (mA): 0

Minutes remaining for full charge: -1