What are you really measuring as a battery discharges?

  • Thread starter ptownbro
  • Start date
  • #1
60
0

Main Question or Discussion Point

Think for example a phone or any devices that shows the amount of battery power is left. It shows it as a graphic where you can deem whether it's full, 3/4 full, 1/2 full, 1/4 etc... or shows the actual percentage. What is that measure really showing you? Voltage? Amp hours left (which is the capacity I think)? And, how is it calculated?
 

Answers and Replies

  • #2
meBigGuy
Gold Member
2,323
405
As a battery discharges the voltage drops under load. This is mostly due to internal resistance increase.
http://www.mpoweruk.com/soc.htm discusses it. It's possible to monitor this externally.

But. most LI-ion batteries have an internal monitoring circuit that reports charge and discharge data back to the operating system. This is best because the data is so battery dependent.
 

Related Threads on What are you really measuring as a battery discharges?

Replies
4
Views
1K
  • Last Post
Replies
2
Views
1K
  • Last Post
Replies
2
Views
3K
Replies
12
Views
2K
Replies
7
Views
1K
Replies
14
Views
520
Replies
15
Views
724
Replies
26
Views
1K
Replies
4
Views
1K
Replies
16
Views
46K
Top