Power distribution & battery estimation

[Bukitoo]

Any hint to develop power distribution on a embedded system ?! (I mean shut down power to non user functional blocks)

Do you know how to estimate de battery life just looking for its voltage?

Thanks in advance

 

[artem]

you can fid few battery related tutors and application notes at site :
**broken link removed**

BTW, battery life is not estimated from its voltage but from chemical elements it is built . If you mean battery capacity - that is amount of energy you can draw from battery. Capacity is measured in amper hour - means how many hours the battery will source 1 amper at its nominal voltage.

 

[Bukitoo]

OK, I know that, but I would like to estimate battery life whit its terminal voltage. Do you know some method/Algorithm ?

 

[mostafa_et]

As far as I know, every battery type has a characteristic curve (aka discharge curve), i.e. a curve of its terminal voltage against time at a certain current draw, which means lets assume you are drawing 100 mA from a certain battery, the curve for 100 mA current draw will show the terminal voltage against time, thus for a given terminal voltage you can know how much time (how much capacity) is left in the battery. The battery characteristic curve should be available from the manufacturer.

Check this link from duracell for datasheets of various battery models
https://www.duracell.com/oem/productdata/default.asp

If the datasheet for your battery is not available, you can maybe setup a circuit with a microcontroller and an analog to digital converter, the circuit should draw a certain current from the battery, and the microcontroller will measure the battery terminal voltage using the ADC at fixed time intervals and use this data to plot the curve. Repeat for various current draw and you've got your battery discharge curves.
I hope this helps.