Tag Archives: i2c

Batteries

The humble Smart Battery reveals its secrets

1 Comment

It took me a little longer than I’d hoped, but I’m able to get most of the information I want out of most of the laptop batteries I’ve tested.

ASUS AL32-1005

Manufacturer Name: AS085NJ35E
Device Name: 1005-28
Chemistry LGC0
Design Capacity (mAh): 5400
Design Voltage: 11250
Manufacture Date (Y-M-D): 2009-6-21
Serial Number: 937
Specification Info: 49
Cycle Count: 254
Voltage: 10.28
Full Charge Capacity (mAh): 1680
Remaining Capacity (mAh): 0
Relative Charge PCT: 0
Absolute Charge: 0
Minutes remaining for full charge: -1
Cell 1 Voltage: 2642
Cell 2 Voltage: 3820
Cell 3 Voltage: 3817
Cell 4 Voltage: 0
State of Health: 0
Charging Current: 0
Charging Voltage: 0
Temp: 20.25
Current (mA): 0

You’ll see that this pack is 5 years old, and has had 254 cycles, which probably puts it near the end of its useful life. Looking at the individual cell voltages (actually banks of parallel cells), you’ll see that that one of them is quite a bit lower than the others, suggesting those cells are closer to failing.
I’m still having trouble with the Dell packs I’ve tested. I can get most of the information I want from them, but they don’t report the capacity of the individual cells properly. The individual cell data isn’t part of the official smart battery standard, but it seems pretty standardized. It may be the Dell packs don’t report that information at all, or it may be that they use a different set of commands to reveal it.

Dell 9T48V

Dell 9T48V
Manufacturer Name: SMP-SDI2.8
Device Name: DELL YXVK234J
Chemistry LION
Design Capacity (mAh): 8400
Design Voltage: 11100
Manufacture Date (Y-M-D): 2013-4-19
Serial Number: 181
Specification Info: 49
Cycle Count: 44
Voltage: 10.03
Full Charge Capacity (mAh): 8428
Remaining Capacity (mAh): 0
Relative Charge PCT: 0
Absolute Charge: 0
Minutes remaining for full charge: -1
Cell 1 Voltage: -1
Cell 2 Voltage: -1
Cell 3 Voltage: -1
Cell 4 Voltage: -1
State of Health: -1
Charging Current: 4214
Charging Voltage: 12900
Temp: 23.25
Current (mA): 0

HP Packs have been a mixed bag. I’ve been able to get a full compliment of data out of some of them, and none at all out of others. I’ll work on fixing it after the initial release.

The code runs on an arduino Yun now, and should be easily adapted to any arduino compatible. I’m going to write a little documentation and release it while I continue to work on it.  If you are interested in getting early access, leave a comment here.