Preliminary demonstration of the early-stage detection of lithium plating for cell blocks based on charge curve analysis data

Kenichiroh KOSHIKA (NTSEL)･Hideki TSURUGA (JET)･Tomokazu MORITA (TOSHIBA)･Keizoh HONDA (JET)

A method for detecting the early stage of lithium plating within cell blocks was investigated using charge curve analysis. The early stage of lithium plating was estimated based on the charge curve analysis data, such as, negative electrode capacity and Shift of operating window (SOW) capacity. Disassembly inspections of the negative electrode and thermal runaway tests on cells were conducted to confirm the early stage of lithium plating within cell blocks.

Demonstrating the influence of lithium plating on thermal propagation and lithium plating occurring in mechanically constrained cells

Keizoh HONDA･Hideki TSURUGA (JET)･Tomokazu MORITA (TOSHIBA)･Kenichiroh KOSHIKA (NTSEL)

Two laboratory-level tests were conducted to reveal the impact of lithium plating on thermal propagation and to demonstrate that mechanical constraint for a cell causes lithium plating within cells. In a thermal propagation test, thermal runaway propagated to an adjacent cell with lithium plating in a shorter period than to an adjacent cell without lithium plating. Compared to unconstrained cells, constrained cells exhibited capacity degradation after fewer charge-discharge cycles and caused lithium plating on the negative electrode.

State Estimation Technology for Battery Systems Incorporating Physical Model Information

Hiroki Nagano･Tenyu Yan･Akira Shoji (Mazda)･Takashi Utsunomiya･Yasuhiro Makino･Shin Wakitani･Toru Yamamoto (Hiroshima University)

In order to enhance the value of electric vehicles and contribute to carbon neutrality and power stabilization, we are developing control technology that can extend the lifespan of battery systems. This paper reports on state estimation technology in battery systems, in which physical model information of the battery is incorporated into equivalent circuit models, enabling high-accuracy estimation of internal states even under degradation.

Battery development for third-generation new EV

Hanae Tsurita･Sadahiro Nagasaka･Ryo Sakamoto･Kenji Hosaka･Norihiko Hirata (Nissan Motor)

The new EV has developed a technological strategy aimed at the full-scale adoption of EVs, focusing on balancing optimal capacity and high efficiency. By leveraging Big Data analysis based on market requirement assessments, the strategy includes capacity optimization, an Intelligent Route Planner (IRP) capable of highly accurate predictions of arrival times and remaining SOC, and integrated thermal management to improve energy efficiency and charging performance. This combination achieves a high-level balance among performance, cost, and convenience.