Modelling the impact of variations in electrode manufacturing on lithium-ion battery modules

The performance of a lithium-ion battery is closely related to its manufacturing and can be impacted by variability in the electrodes. Typically, manufacturers must set aside cells which are deemed to be of insufficient quality, thus contributing to the cost of manufacturing high quality cells. The performance of a lithium-ion battery module, that is, a string of cells configured in series, depends on the performance of the weakest cell. In this work, the single particle model was adapted to simulate the coupled behaviour of an arbitrary number of cells configured in series. The impact of slight variations in the manufacturing of electrodes was then investigated with a goal of linking electrode properties such as variations in thickness, electrode density and active material weight fraction with the performance of battery modules made from these cells. Results indicate that the initial capacity, the rate of capacity fade and other important aspects such as the distribution of state-of-charge from one cell to another depends on the extent of variability in the manufacturing of the electrodes. In this work, the variation in the performance of the module has been quantified as a function of manufacturing variation at the electrode level.