PackProbe (alpha) for dumping data from laptop packs

[eas]

@ginbot86

Excellent project and idea; there definitely isn’t enough attention out there in terms of being able to read out the diagnostic information in smart battery packs!

In terms of your last post, the cell/pack voltage isn’t a good determining factor for estimating the capacity/state of health of a Li-ion battery pack (with exception to very low cell voltages), but is instead related to cell state of charge.

Agreed, but, some people seem to go further and take higher voltages as the sign of a good cell/pack, perhaps because its a sign of low self-discharge. I may be overestimating the extent and influence of this thinking, in thinking it was worth presenting evidence against it.

@ginbot86

Now, in regards to the code, the Time-to-Full/Empty (the Minutes remaining readout in the PackProbe software) commands are actually _un_signed shorts (16-bit integers), with 0xFFFF (shown as –1 in your code) meaning ‘N/A’. Also, note that the State of Health command is non-standard as the official SBS specs don’t have it in the list.
(edit: Removed “as the” from 3rd paragraph)

Thanks! I really appreciate the troubleshooting.

Not sure where I got the SoH command from now. I had to do some digging to find the non-standard commands for individual cell/bank voltages, and probably came across that along the way.

I need to sit down and take stock of everything I’ve learned and figure out the best path to future releases. There are some little one-off-fixes I can make, but I think they’d be easier to make and maintain in the long run if I refactored to achieve some other goals too…

[snakebite]

next up?
a usb to universal pack interface.
if you have the laptop the packs match one can also use this
bt i got a new as in charged 1 time,never cycled and put in a desk drawer pack from early 2012.
all 3 pairs were at 4.01v.
my neighbor sent his new at the time toshiba laptop in for warranty repair and got it back with a new in box extra pack.sold the laptop and forgot the pack till now.hey can you take this to work and recycle it?
sure!.
those are panasonic cgr18650cg and tested at 2a discharge at 2358mah each ± 5 mah!
they were still around 85% after more than 2 years after a charge and once fully charged were still like new.

[ginbot86]

@ruffles

Welcome to BLF, ginbot86. That’s a heck of a first post!

Thanks, glad to be here!

I’ve done quite a bit of work with this sort of Li-ion battery fuel gauge stuff (heck, it landed me a trip down to Dallas for a Texas Instruments battery-management seminar back in October!). Granted, the chips I usually work with are single-cell (1S) fuel gauges from Texas Instruments with a less-standard protocol, but many of the things there apply to laptop SBS systems. As an example of this, not too long ago, I wrote software that harnesses a modified PC serial port and can read out batteries that use the HDQ protocol (for example, iPhone batteries).

Given how PackProbe is an open-source project, I can probably contribute some code with regards to, for example, interpreting the Battery Status and Battery Mode commands, something like:

Battery Status = 0x00C0
Battery Status interpretation:

• Battery is operating normally (no alarm bits set)
• Battery gauge is initialized
• Battery is discharging
• No error codes detected

Battery Mode = 0xE081
Battery Mode interpretation:

• Battery capacity is reported in centiwatt-hours, not milliamp-hours
• SMBus broadcasting of charge voltage/current is disabled (controller must poll the battery to read charge recommendations)
• SMBus broadcasting of battery alarms are disabled
• Configured as a secondary battery, and primary battery functionality is not supported
• Charge controller functionality is supported, but disabled
• Reported battery capacity may be inaccurate (perform a learning cycle by doing a full charge-discharge cycle)