Study on equivalent circuit model of lithium titanate battery for rail transit

Recently, lithium titanate batteries have been widely used in energy storage systems, because of their attractive performance and environmentally friendly characteristics. Regarding the state estimation of lithium titanate batteries used in the new energy rail transit vehicles, the research work accomplished in our study mainly includes model-driven state estimation method on short time scale, and ageing mechanisms analysis based on state estimation result on long time scale. The experiments were conducted under constant current and UDDS dynamic conditions using three types of lithium titanate batteries. The results indicate that the maximum voltage error of our new battery model and estimation method is less than 2%.