A critical review of using the Peukert equation for determining the remaining capacity of lead-acid and lithium-ion batteries 

Abu-Sharkh, Suleiman; Doerffel, Dennis (2006) In: Journal of Power Sources, Volume 155, Issue 2 , 21 April 2006, Pages 395-400 (doi:10.1016/j.jpowsour.2005.04.030)

In many applications it is essential to predict the remaining capacity of a battery reliably, accurately and simply. Several existing techniques for predicting the remaining capacity of a lead-acid battery discharged with a variable current are based on variants of Peukert's empirical equation, which relates the available capacity to a constant discharge current. This paper presents a critical review of these techniques in the light of experimental tests that were carried out on two lead-acid commercial batteries. The relevance of these Peukert's equation based techniques to lithium-ion batteries is also discussed in the light of tests carried on a lithium-ion power battery. The basic conclusion of the paper is that Peukert's equation cannot be used to predict the state of charge of a battery accurately unless it is discharged at a constant current and constant temperature.

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