Measurement-Based Development of High-Fidelity Electrochemical Models for LFP Cells

Takatoshi Hasegawa･Ryotaro Miyazaki･Kazunao Takahashi･Kengo Araki･Tomomi Ejima (IDAJ)･Hironobu Tsuji･Hirofumi Moriwaki (Toray Research Center)

In battery-powered product development, electrochemical models are increasingly used, but methods for obtaining required parameters are not yet well established, and electrochemical parameters are often treated as tuning terms. In this work, we constructed a detailed measurement-based electrochemical model and demonstrate its value and importance.

Environmental Footprint of Aluminum and Steel BEV Battery Pack Structures under Equivalent Crash Performance

Shun Takenaka･Shuki Nakamura･Shota Chinzei (Kobe Steel)･Hatsumi Yoshino (Kobelco Business Partners)･Kazuyuki Hamada･Kenichi Watanabe･Masatoshi Yoshida (Kobe Steel)

Driven by increasing demand for environmental impact reduction, battery packs are required to simultaneously ensure crash safety and minimize environmental burdens. In this study, battery pack structures made of aluminum alloy and steel were designed to achieve equivalent crash performance under identical vehicle conditions, and their weight and environmental impacts over the life cycle were quantitatively evaluated.

Study on Improving Cycle Durability of Anode-free All-solid-state Batteries
-(Second Report)-

Takashi Nakagawa･Kyohei Izumi･Shuntaro Ujiie･Hayate Kusushita･Kenta Nagamine (Honda R&D)

Degradation analysis of anode-free all solid-state batteries and improvement of charge-discharge cycle durability by improving the specification of anode current collection foil will be reported.

Experimental Evaluation of Thermal Runaway and Thermal Propagation Behavior in Lithium-Plated Cells Using Laser Irradiation

Kenichiroh Koshika (NALTEC)･Hideki Tsuruga (JET)･Tomokazu Morita (Toshiba)･Keizoh Honda (JET)

This study evaluates the thermal runaway and thermal propagation behavior of lithium-plated cells using a laser irradiation method. Single-cell tests were conducted to compare the onset characteristics of thermal runaway, while propagation tests were performed using configurations of adjacent cells. The results demonstrate that lithium plating promotes the initiation of thermal runaway and significantly enhances the likelihood of thermal propagation between cells, indicating a reduction in battery safety associated with lithium plating.

SOH and Cell Balance Estimation Using Non-Destructive Diagnostics During Cycle Aging of a Battery Pack Emulating Repurposed Use

Tomokazu Morita (Toshiba)･Kenichiroh Koshika (NALTEC)･Hideki Tsuruga･Keizoh Honda (JET)

A battery pack emulating a repurposed battery, composed of cells with different degradation histories, was fabricated, and cycle degradation tests were conducted. As a non-destructive diagnostic method to estimate the state of health (SOH) and cell balance of the battery pack and each cell, the degradation state of the battery pack was estimated using charging curve analysis and estimation methods based on cell OCV-SOC. The estimation accuracy was evaluated by comparing the estimation results with the measured capacity of the battery pack.