Rechargeable batteries are energy storage devices that can be recharged and discharged repeatedly and are used in a wide range of applications, including electronic devices, electrically power-assisted bicycles, renewable energy storage, and electric vehicles (EVs). They also play an essential role in the energy transition towards de-fossilization, and their use is expected to expand. The life cycle of rechargeable batteries includes the processes from raw material sourcing and procurement to manufacturing, use, disposal, and recycling, and environmental impact assessments are carried out using life cycle assessment (LCA). In particular, lithium-ion batteries (LIBs) are a major type of rechargeable battery, and the choice of cathode and anode materials and electrolytes has a significant impact on performance and environmental impact. Previous studies using LCA have shown that the type of cathode active material, manufacturing technology, and unit power consumption impact the results. During the use phase, the efficiency of charging and discharging and the matching effect of the application have a significant impact. While the introduction of EVs contributes to reducing environmental impact, the effect of this varies depending on the power source composition and the state of the charging infrastructure. In addition, stationary applications such as hydrogen production and solar power generation are also being considered. In the disposal and recycling stage, technologies and processes for recovering metal resources are diversified, and direct recycling and hydrometallurgy are being compared. It is important to select the right recycling technology to reduce environmental impact. In the future, in light of the rapid progress of secondary battery technology, it will be necessary to establish appropriate evaluation criteria and design sustainable systems.

In response to global warming concerns, there is an accelerating transition toward Electric Vehicles (EVs) worldwide. EVs offer potential for a circular economy across multiple phases: new vehicle manufacturing, used car distribution, battery repurposing, and recycling. This article examines Japan’s EV market challenges and prospects from a circular economy perspective. Currently, about 80% of used EVs in Japan are exported overseas, creating a bottleneck in the circular economy system. This is driven by structural issues including concerns about battery performance and lack of market transparency. To address these challenges, solutions such as establishing battery performance evaluation standards and implementing residual value guarantee programs are proposed.

1 Zeroboard Inc. The carbon footprint of products (CFP) has been used as a means of comprehensively and quantitatively indicating the impact of the product on climate change. However, it is too difficult to establish unified calculation methods, so it has not been used as a concrete legal regulation. Recently, as the information infrastructure for calculating CFP has been prepared and a rough consensus can be reached, a movement to use the calculation results in regulations has begun in Europe. Therefore, I have reviewed the contents of the following three European laws and regulations: 1) Carbon Boarder Adjustment Mechanism (CBAM), 2) European Battery Regulation and 3) Ecodesign for Sustainable Products Regulation (ESPR), and considered the measures that will be required in the future.

The objective of this paper is proposing Smart Use approach, from the use side of market, to solve the issues of market incubation of Circular Economy for electric vehicles (EV) and battery, which has been rapidly expanding in recent years. Currently, there are various issues in the EV battery circular economy market in Japan. Many of these issues are caused by insecurity during use. Therefore, it is necessary to improve not only the supply side, such as recycling methods and reused battery production, but also the use side. Improvements to these issues include methods such as using battery diagnostics and other technologies to understand the condition of the batteries, thereby reducing user anxiety and supporting active use by the users. The circular economy creates new markets by maximizing the use value of products and resources so as not to generate waste. Smart use is one of the approaches to maximize such use value from the user side, and it is an approach that draws out positive actions from users by utilizing advanced IoT and other digital technologies etc. We aim for the early formation of a domestic market by concretizing solutions and promoting their widespread use.

With the increasing adoption of electric vehicles (EVs), a surge in first end-of-life (FEoL) lithium-ion batteries (LiBs) is expected to become available for either treatment or further use. Since recycling processes are currently insufficient to meet treatment demands in a sufficiently sustainable way, repurposing LiBs for less demanding applications, such as household energy storage systems (ESS), may offer significant economic and environmental benefits. This paper explores the potential for establishing circular value chains for LiBs, focusing on the ecosystem required for their repurposing. Key stakeholders in the value chain are identified, and examples from retail and original equipment manufacturer (OEM) perspectives are discussed. Barriers and opportunities for further development are briefly discussed, with recommendations for future research to ensure a robust, circular system for LiB repurposing.