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The integration of cells that exhibit differing electrical characteristics, such as variations in energy capacity and internal resistance can degrade the overall performance of the energy storage system (ESS) when those cells are aggregated into single battery pack. When cells are connected electrically in parallel, such variations can lead to significant individual differences in battery load current, state of charge (SOC) and heat generation. Further, if consideration is given to small variations in cell interconnection resistance, the detrimental effect on load imbalance is amplified. Given that cell resistance is known to be a function of both SOC and temperature, the impact of the imbalance is compounded as the performance of cells further diverge under load. During extended periods of excitation, variations in cell depth of discharge (DOD) and the occurrence of temperature gradients across the parallel connection will …