New strategy for battery sizing regarding the impact of discharge durations on its capacity

Lead-Acid batteries (LAB) are among the most commonly used in grid and industry applications. The capacity of a battery determines how much energy it can inject to/ absorb from the grid. Among various battery technologies, the LAB is widely used than the others. Various technologies have addressed LAB sizing for different applications including peak-shaving, operational cost reduction and etc. They have assumed the LAB capacity to be constant under different discharge durations, which is wrong. This could lead to over-sizing or under-sizing that results in increased cost or battery damage, respectively. In reality, the useable and effective LAB capacity decreases as the discharge current increases and discharge duration decreases. Here, a novel methodology is proposed to determine the LAB capacity considering the impact of the discharge duration on the useable and effective LAB capacity. The proposed methodology is used for peak shaving in an islanded MG.