# How to Calculate Battery Capacity, Discharge Time using Peukert's Law - Tutorial

## How to Calculate Battery Capacity, Discharge Time using Peukert's Law - Tutorial, Definition, Formula, Example

#### Definition:

Peukert's law is the widely used empirical equation to denote the rate-dependent capacity which illustrates an exponential relationship between the discharge current and delivered capacity, over specified range of discharge currents.

This tutorial explains how to calculate the Battery Capacity, Discharge Time using Peukert's Law.

#### Formula:

Actual Battery Capacity = (C x I) / In Peukert's Formula, T = C / In Where, C = Rated Battery Capacity I = Rate of Discharge n = Peukert's Number T = Full Discharge Time

#### Example :

The rated battery charge capacity is 250 amp-hours, discharge rate is 20 amps and peukert's number is 1.3, what is the actual battery capacity and discharge time.

#### Given :

Rated Battery Capacity (C) = 250 amp-hours
Rate of Discharge (I) = 20 amps
Peukert's Number (n) = 1.3

#### To Find :

Actual Battery Capacity and Full Discharge Time

#### Solution :

Substitute the given values in the formula,

Actual Battery Capacity Calculation
 Actual Battery Capacity = (C x I) / In = (250 x 20) / 201.3 = 5000 / 49.129121045 = 101.772632884
Full Discharge Time Calculation
 Full Discharge Time (T) = C / In = 250 / 201.3 = 250 / 49.129121045 = 5.088631644