Battery discharge rate

The charge and discharge current of a battery is measured in
C-rate
Most portable batteries are rated at 1C.
In Idea Case:
A Battery has a capacity of 1000mAh will discharge at 1C to provide 1000mA for 1 hour. The 1000mAh battery will also discharge at 0.5C to provide 500mA for 2hrs. At 2C, the battery will provide 2000mA for 0.5hr.
The calculation showed the relationship between discharge rate, the time and the capacity in an ideal case.
However due to internal energy loss and voltage drop, the battery will perform better with a smaller discharge rate.
In Real Case:
At 1C, a 10Ah lead acid battery discharges at the 10A in less than one hour.
圖片參考：http://www.batteryuniversity.com/images/partone-16a1.jpg




Discharge current
C-Rate
Discharge time
End of discharge

Table 2: Typical discharge times of a 10Ah lead acid battery as a function of C-rate.

0.5A
0.05C
20h
1.75V/cell

0.1A
0.1C
10h
1.75V/cell

2A
0.2C
5h
1.70V/cell

2.8A
0.28C
3f
1.64V/cell

6A
0.6C
1h
1.55V/cell

10A
1C
0.5h
1.40V/cell