Progress and Challenges in Determining the State of Charge, Power and Health of Battery Systems - (PPT)

摘要

Battery performance is key to vehicle electrification. 1. To optimize trade-offs between performance and life, accurate in-vehicle battery management is needed. To understand the impact of battery design features: 1. (material choice, particle size, electrode thickness, etc.) one models the battery as a system of coupled PDEs, usually (1+1)D. 2. Diffusion is important. A simple model yields Warburg impedance. For in-vehicle powertrain control equivalent circuit models are convenient. 1. R+N(R‖C) ECM Is a useful canonical form. 2. A nonlinear resistor can model the Butler-Volmer effect. 3. N=3 seems to suffice for some present-day Li-ion batteries. Hysteresis in silicon may present substantial challenges in the near future.