Comparison of Series, Parallel and Composite (Series & Parallel) Configurations for Cell Formation Process of Lithium-Ion Cells

The formation chambers are the most important and energy consuming stages during cell formation process, where lithium-ion cells undergo continuous charging and discharging cycles. In this research we are proposing to use composite configuration consisting of 32 cells arranged in 8 parallel assemblies of 4 cells each connected in parallel, whereas these 8 parallel assemblies are connected in series with each other. Simulations and model development have been carried out by using the MATLAB SIMSCAPE library. Lithium-Ion cells are arranged in these three configurations and separately charged and discharged using CC-CV configuration at 0.5C, 1C and 2C charging and discharging rate. We have compared the outputs (SOC, Voltage, Current and Temperature) of proposed composite configuration to the outputs of existing series and parallel configurations to analyze the performance of each configuration.