Hi!

it could be something similar to (I might have made a mistake when applying scaling):

/* calculate remaining fuel level (in %) of a LiIon battery assuming
* a standard chemistry model
*    http://cseweb.ucsd.edu/~trosing/lectures/battery.pdf
*
* @mV: voltage measured outside the battery
* @mA: current flowing out of the battery
* @mOhm: assumed series resitance of the battery
*
* returns value between 0 and 100
*/

static inline int fuel_level_LiIon(int mV, int mA, int mOhm) {
	int u;
	/* internal battery voltage is higher than measured */

add " when discharging".

	mV += (mOhm * mA) /1000;

	/* apply formula */
 	u = 3870000 - (14523 * (37835 - 10 * mV));

	/* linear approximation between 3.756V */

	if (u < 0)
		return ((mV - 3300) * ((3756 - 3300) * 1966)) / 100000;
	return (1966 + sqrt(u))/100;
}

Thanks,
									Pavel

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