-   Linux - Newbie (
-   -   Battery Remaining Capacity (

jay_manikandan 10-17-2007 03:25 AM

Battery Remaining Capacity

I am writing an application to find the current battery capacity in the driver level.
My board has Li_Ion battery.

I can get the following parameters from the battery driver:
1) Voltage
2) Current
3) Temperature.

I have to find out the remaining battery capacity with the above params.
I read some article which says we have to consider 1)temperature derate factor and 2)depth of discharge to calculate the capacity with accuracy.

Please help me in this regard.

I have gone through the posts made in this forum. All the posts are
discussing about /proc/acpi filesystems.
But my case is different.


Findus 10-17-2007 03:45 AM

Maybe you could specify in what regards your case is different? I can't help you, as I am not much of a programmer, but that information might help some one who can to give you more specific help.

- Findus

jay_manikandan 10-17-2007 04:01 AM

I have to find out the remaining battery capacity without /proc/acpi file system.
I have to use the following parameters to calculate the battery capacity.
1) Voltage
2) Current
3) Temperature.

I read in an article to find the current battery energy in Watt-Hours.

E = C * Vavg * (tempdefactor/100) * (depthdischarge/100)

tempdefactor -> Temperate derating factor
depth discharge -> depth of discharge.

Can i use this formula to calculate the current available energy of a battery?
If so, what value i can use for tempdefacor and depthdischarge?
Is there any spec or tables to find out these values based on temperature and ageing?

Hope am not confusing you.

All times are GMT -5. The time now is 09:24 AM.