Sensitivity Analysis on Charging Condition and Operating SOC Range to Degradation of LFP-type lithium-ion Battery

Kenichiroh Koshika (NTSEL)･Hideki Tsuruga (JET)･Tomokazu Morita (TOSHIBA)･Keizoh Honda (JET)

A sensitivity analysis was conducted on the effect of charging condition and operating SOC range to degradation of LFP-type lithium-ion battery as a basic study for field research planed in near future. The battery degradation was evaluated from two perspective: SOH (state of health) and SOS (state of safety). Repeated charge-discharge in a combination condition of a low temperature, fast charging and operating high SOC area, caused a rapid decline in battery capacity and an increased risk of thermal runaway. Chemical analysis for disassemble cells was also conducted to investigate the cause of the increased risk of thermal runaway.

Charge-Discharge Behavior and Safety Evaluation of Pouch-type Lithium-ion Battery using Laminated Steel Sheets for Cell Case

Misaki Masatsugu･Shintaro Yamanaka･Takehiro Takahashi･Yasuto Goto (Nippon Steel)

We have investigated the use of laminated steel sheets for cell case to improve the impact resistance of pouch-type lithium-ion battery. In this study, a pouch-type Lithium-ion battery using laminated steel sheets for cell case was made and its charge-discharge behavior and safety by crushing test using a round bar was evaluated, which showed good results.

Study of Optimal Thermal Management System for Battery based on Vehicle System 1D Simulation Model (Second Report)

Yuya Hato･Poyuan Liu･Wei-Hsiang Yang･Toshio Hirota･Yushi Kamiya (Waseda University)･Kiyotaka Sato (Mazda)

Thermal management for the lithium-ion battery in the electric vehicle, which controls the battery temperature, is important to counteract power output and degradation of the battery. To design an optimal thermal management system, it is effective to use a vehicle system 1D simulation model. In the first report, we proposed optimal thermal management system for BEVs. In this report, we tested the system's cooling and fast-charging performance, which are issues for BEVs using the vehicle system 1D simulation model.

Evaluation of Thermal Runaway Propagation of Prismatic Lithium Ion Battery, whose Cell Case Was Made by Steel

Kosuke Kawamoto･Yasuto Goto (Nippon Steel)･Tatsuo Nagata (Nippon Steel Technology)

Aluminum is the main material of cell case of prismatic lithium-ion battery, but using nickel electroplating steel sheets is expected to improve safety, increase volumetric energy density, reduce costs, and so on. In this study, a prismatic lithium-ion battery using a nickel electroplating steel plate as a cell case was fabricated, and when thermal runaway propagation was evaluated, it was confirmed that thermal runaway time was extended.