Basic study of model based development of lithium-ion battery using Co-simulation of vehicle system model and electrochemical cell model

Abstract

Lithium-ion batteries are widely used for various applications in mechanical system. Requirements that battery should meet depend on the its application, and have wide variety such as high energy density or high input-output power. To develop a battery, iteration of prototyping and testing is required in each layer of cell, module and system and it takes time. Aiming to shorten development time, we propose system simulator that consists of electrochemical cell model of lithium-ion battery and 1D model of mechanical system. The feature of an electrochemical model is that it uses the design parameter of battery cells, such as electrode composition and thickness, as a variable of model equation. This enables us to predict performance of the cell that installed to the system before cell module and system fabrication, and to reduce lead time. In this paper, we introduce a case of hybrid electric vehicle. The simulation results showed that cell design which enlarges capacity was not the optimal way in the voltage performance when vehicle runs in World-wide harmonized Light duty driving Test Cycles (WLTC).