Japan launches EV battery diagnostic service to boost safe circularity

JA Mitsui Leasing Group, denchi.ai Co., Ltd. and NIHON AUTO RECYCLE have begun full-scale operations of a new diagnostic and discharge service for end-of-life batteries from electric and hybrid vehicles. The service was officially launched on 17 November following joint demonstration trials, and aims to promote resource circulation through more accurate battery valuation while reducing fire risks at recycling sites.

A key feature of the service is the use of denchi’s portable diagnostic device. The system employs electrochemical impedance spectroscopy, a non-destructive method that directly measures internal battery degradation. This allows for more accurate State of Health (SOH) assessments than conventional indicators such as mileage or model year, supporting proper decisions on reuse, repurposing and recycling. Diagnostics can be performed quickly and on-site at recycling facilities, used-car dealerships and repair workshops.

The device also features a discharge function. By safely discharging batteries before they enter the recycling process, it significantly lowers the risk of fires, an increasingly serious issue at recycling facilities, and enables safe storage and transport.

The companies developed the service in response to emerging challenges linked to the wider adoption of electric vehicles. Japan’s Ministry of Economy, Trade and Industry (METI) forecast in its March 2023 Growth-Oriented, Resource-Autonomous Circular Economy Strategy that the circular economy market could reach 80 trillion yen by 2030, underlining the strategic importance of battery resource recovery. Yet the lack of standardised performance evaluation criteria for used batteries has depressed the market value of second-hand EVs compared with petrol vehicles. As a result, many EVs with high-value batteries are exported rather than reused domestically.

Recycling sites are also facing mounting operational issues. Large quantities of dismantled batteries are often stored for extended periods without adequate evaluation or processing systems in place, creating heightened fire risks and straining storage capacity.

The new service is the result of repeated demonstration trials using batteries collected from end-of-lease vehicles and scrapped cars, through which the partners established diagnostic and discharge processes compatible with multiple vehicle types. JA Mitsui Leasing Group oversaw the planning and coordination of the trials, denchi handled technology development and data analysis, and NIHON AUTO RECYCLE provided the testing environment.

The partners plan to further enhance the diagnostic and discharge technologies while building a nationwide service framework.

Originally published on Circular Economy Hub.