Peukert dependencies

Figure 6.26 presents the Peukert dependences for the above batteries. With increase of the water content in the semi-suspension, the Peukert curves shift towards higher specific capacity values. 

The plates described in Table 8.1 were assembled in 12V/34 Ah batteries that were set to tests at 42% utihzation of the positive active mass. Beside the initial capacity at 20 h discharge rate (all batteries met the requirements of this test), the Peukert dependences for these batteries... 

Peukert dependences for batteries with positive plates produced by the curing methods... 

This energy is measured not only in Joules (1 J = 1 W s) but also in watt-hours (1 Wh = 3600 J.). Both the maximum ampere-hour capacity and the watt-hour energy depend on the amount of reactants in a battery at the start of discharge. As the discharge current increases, both the discharge voltage and the reactant utilization coefficient diminish. A number of attempts to find a relationship between the actual battery capacity and the discharge current were reported. An approximation found in 1897 by Peukert for lead acid batteries is sometimes used ... 

C. Binder, M.A.J. Haitig, W. Peukert, Structural dependent drag force and orientation prediction for small fractal aggregates. J. Colloid Interface Sci. 331(1), 243-250 (2009). doi 10.1016/j. jcis.2008.11.021... 

W. Dependency of the capacity on the discharge current and the temperature. Peukert s law... 

So long as the discharge currents remain reasonable (around 1 C), the capacity depends only very little, if at all, on the regime of discharge, but appears to be more sensitive to temperature than is the case for a lead-acid battery. Peukert s law, introduced for lead-acid batteries, describes the dependency of the capacity on the discharge current. It is expressed thus ... 

This Peukert coefficient, close to 1, giving a capacity independent of the duration of discharge, may lead us to choose a linear model of the dependency of the capacity on the discharge current. For instance, for an NCA element with poor capacity, we find the following values at 25°C C= 10.5 (Ah)-0.276.1 (A). 

Many empirical expressions have been proposed in the literature for the capac-ity/current dependence, but only that formulated by Peukert in 1898 has found wide acceptance ... 

In the early 1990s, an empirical model was developed by Roan and Raman [22] in order to provide a fast executing battery performance simulation model that could be used as a subroutine in HEV and EV simulation codes. The current effect on battery capacity has been modeled by Peukert s equation (Equation 9.26) and the temperature effect by Equation 9.31. Available cycle life data for LABs suggests that the cycle life depends strongly on DOD and has been modeled by the following equation ... 

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