Battery recovery issues

Richard A. Smith richard at
Wed Apr 29 13:25:08 EDT 2009

Emiliano Pastorino wrote:
>     Are you using the latest batman.fth?  I pulled a lot of batman
>     functionality into the firmware and had to modify batman.fth to
>     avoid the errors above.
> I'm using  0.3.6.

Sorry.  I didn't have the latest up on the site.  Grab a fresh copy.

> Is there any up-to-date document on how to proceed when recovering a 
> faulty battery  using recent firmware?

No. But the difference is just running batman-start prior to 
bat-recover.  If you want to stop bat-recover then remove the battery. 
It will error and drop to an ok prompt.

> Should I expect any output when running batman-start? I noticed that 
> battery interface is suspended,  but I don't see anything else
> going on.

Nope. And while batman is enabled don't expect the charge LED to do 
anything normal. It will flash in odd patterns.

> Now I'm trying to recover a red led flashing battery. Suddenly, it went 
> from flashing red to nothing and I'm also getting "No battery" from 
> "watch-battery"
> and 0 1 2 0 1 2..... from "see-bstat".
> When the led was flashing red, I could get an error code of "2" from 
> "ec-abnormal@ .". Now I'm getting "0". I'd like to know what that 2 
> meant. Where
> can I get the explanation of those error codes?

The error list on the wiki is a bit out of date.  I'll work on updating 
a list on the battery diagnostics page.  A 2 mean that the status 
register setting in the battery gas gauge was not what the EC expected 
it to be.  This happens every so often and is usually transient.  If it 
was actually written into the EEPROM and you get that every time then 
please do a bat-dump-banks and look at the value in the 2nd line of 
bank0, Col 1. It should be 0x6a if is not then you can use 
bat-set-status to fix it.

ok batman-start
ok 6a bat-set-status
ok batman-stop

> I'll be testing more faulty batteries, so I'll be bothering here 
> periodically :)

No problem.  Please help me keep the battery diagnostic page up to date 
with things that you find.

On that note.  I need to get with you sometime and get some charge logs. 
    I'm want to know how the capacity of the batteries you have had out 
in the field are holding up.

Richard Smith  <richard at>
One Laptop Per Child

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