Product selection guide

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Lithium Battery use period

Generally ‘Ahr’ is used as a capacity unit and could be calculated by multiplying the use current [A] and time [Hr]. So, in case of battery of having the same capacity, as the discharge current increases the use time would be decreased.

Use time at the constant current discharge situation

If we assume the nominal capacity 2Ahr battery and 10mA of current value

Battery use time [hr] is
=nominal capacity [Ahr]/use current [A]
-2Ahr/0.01A = 200hr

in other words, the battery capacity same as the area of the right diagram.
Use time at the pulse discharge situation

If we assume that the battery's nominal capacity 2Ahr and set a base current 1mA, 1st pulse discharge rate of 5mA per 5sec, 2nd pulse discharge rate of 20ma per 1sec and continue the discharge cycle for 10 sec interval

Consumption capacity [Ahr] per 1 cycle is
= Area below the current curve of 1cycle
= Area A + Area B + Area C
={(0.02-0.005) x 1/3600} + {(0.005-0.001) x 5/3600} + {(0.001x10/3600}
= 0.0000125Ahr, And

Use time [hr] is
=Cycle number x Time [hr] per 1cycle
=Nominal capacity [Ahr] / Use capacity[Ahr]per 1cycle x Time [hr] per 1cycle
=2Ahr/0.0000125Ahr x 10/3600hr = 444hr

But, the above use time is the optimal value of calculation and the use time could be varied depends on below conditions.

  • Self discharge generation depends on the storage period
  • Use temperature of the battery
  • Use current value of the battery