Idemitsu to Build Lithium Sulphide Plant in Chiba to Support Toyota’s All-Solid-State Battery Rollout

Idemitsu, Lithium Sulphide Plant

$142 Million Facility to Produce Key ASSB Material for 3GWh Annually, Backed by Japanese Government Subsidies

Idemitsu Advances Battery Strategy with New Lithium Sulphide Facility

Japanese energy firm Idemitsu Kosan has announced plans to construct a large-scale lithium sulphide production plant in Chiba, with completion targeted for June 2027. The project is part of Idemitsu’s broader strategy to establish an integrated supply chain for all-solid-state battery (ASSB) production—a technology expected to define the next generation of electric vehicle (EV) batteries.

The plant will produce lithium sulphide at volumes equivalent to powering 3GWh of ASSB output annually, reinforcing Japan’s position in the global battery supply chain. The ¥21.3 billion ($142 million) investment will be partially supported by ¥7.1 billion in government subsidies, according to Idemitsu.

ASSB Seen as Next-Generation EV Battery Solution

ASSBs offer significant advantages over traditional lithium-ion (Li-ion) batteries, including faster charging, higher energy density, better thermal stability, and reduced use of critical metals like nickel and cobalt. These benefits make them highly attractive for next-generation EV platforms.

In October 2023, Idemitsu and Toyota announced a partnership to commercialize ASSB for EVs by 2027–2028. Under this plan, Idemitsu will supply solid electrolytes, derived from its lithium sulphide, while Toyota integrates them into EV battery systems. Toyota’s goal is to produce vehicles capable of driving up to 1,200 km on a single charge—more than twice the range of its current EVs.

Integrated Upstream-Downstream Supply Secures Japan’s Battery Future

Idemitsu will manufacture lithium sulphide by processing lithium hydroxide sourced from its Australian mining assets with sulphur by-products from its oil refining operations. This vertically integrated model reflects Japan’s push to reduce battery supply chain dependencies on China while leveraging domestic expertise in refining and manufacturing.

As Japan’s second-largest oil refiner, Idemitsu is uniquely positioned to transform its fossil fuel legacy into a clean tech future. The company also plans to produce several thousand tonnes of solid electrolyte materials to support full-scale ASSB deployment across Toyota’s production lines.

Japan-Australia Graphite Anode Supply Chain Targets Battery Security

Graphite

The Japan-Australia graphite anode supply chain is becoming a serious strategic project for battery materials security. Idemitsu, Marubeni, NSC, and Graphinex have agreed to develop a cross-border supply chain for natural graphite anode material. The plan links graphite mining in Queensland with refining and processing in Japan. As a result, the Japan-Australia graphite anode supply chain could reduce reliance on more concentrated supply routes.

This matters because graphite remains one of the most important battery raw materials. Demand continues to rise with electric vehicles and renewable energy storage. Japan has relied heavily on imports for graphite procurement. Therefore, the Japan-Australia graphite anode supply chain directly addresses a critical supply risk.

The industrial structure of the deal is also clear. Idemitsu and Graphinex will handle graphite extraction in Australia. Marubeni and NSC will focus on refining and processing in Japan. Consequently, the project is designed as a full upstream-to-midstream partnership rather than a simple trading agreement.

Natural Graphite Anode Material Is Becoming a Strategic Priority

Natural graphite anode material is now central to battery manufacturing competitiveness. Without secure graphite supply, downstream battery production becomes more vulnerable to trade shocks and export restrictions. That makes source diversification more important than ever. As a result, Japan is moving to secure a more stable anode material base.

China’s role helps explain the urgency. Japan wants alternative import sources as it reduces dependence on the world’s largest graphite producer and exporter. Export controls have made that concentration risk harder to ignore. Therefore, the new partnership reflects both industrial logic and geopolitical caution.

Idemitsu’s earlier investment in Graphinex also shows this strategy did not begin overnight. The companies have already been building ties around Australian graphite mining. This new agreement pushes that relationship into a more integrated supply chain phase. Meanwhile, it strengthens confidence that the project has real strategic intent.

Graphite Anode Plant in Japan Could Deepen Domestic Battery Capacity

The graphite anode plant in Japan is the most important downstream element of the plan. The companies are exploring a Japanese production site and aim to start operations in 2028. That would give Japan more domestic control over an essential battery input. Consequently, the graphite anode plant in Japan could become a meaningful industrial anchor.

The partnership also aligns with the wider Japan-Australia critical minerals agenda. Both countries have been working to deepen cooperation on energy security and supply chains. This project fits that framework well because graphite sits at the core of battery manufacturing. Therefore, the deal supports both national policy and commercial demand.

The broader market significance is clear. Battery supply chains are no longer judged only by cell production capacity. They are increasingly judged by who controls upstream and midstream materials. As a result, the Japan-Australia graphite anode supply chain could become a notable model for allied critical mineral cooperation.

The Metalnomist Commentary

This partnership matters because it targets one of the most overlooked battery bottlenecks: graphite anodes. Japan is not only seeking more raw material. It is trying to secure processing and manufacturing depth as well. If execution stays on track, this project could become an important example of how allied supply chains move beyond dependence and into real industrial coordination.

Queensland vanadium electrolyte plant investment backs Australia’s flow battery ambitions

Queensland Vanadium Plant

Queensland vanadium electrolyte plant investment signals a stronger push into long duration energy storage in Australia. The state government has committed A$10mn to Vecco’s Julia Creek mine and Townsville vanadium electrolyte plant. As a result, the Queensland vanadium electrolyte plant investment aims to anchor a domestic supply chain from ore to vanadium redox flow batteries.

Queensland vanadium electrolyte plant investment will support Australia’s first commercial scale electrolyte facility in Townsville. Vecco plans to build a 300 MWh per year plant starting in 2026, with operations targeted for 2028. This will scale up from its existing 35 MWh per year Townsville unit, which already produces vanadium electrolyte. Therefore, Vecco can leverage operational experience as it ramps to larger industrial volumes.

Julia Creek mine links vanadium ore to battery electrolyte

The Julia Creek mine forms the resource backbone of the Queensland vanadium electrolyte plant investment. Vecco plans to open the 8,700 t per year vanadium pentoxide operation in 2027. The mine will supply feedstock directly to the larger Townsville electrolyte plant, closing the loop between mining and chemicals.

This integrated structure reduces reliance on imported vanadium intermediates and marketing risk. Meanwhile, it supports Australia’s broader critical minerals strategy focused on value added processing, not just ore exports. Over the life of the project, Vecco aims to position Julia Creek as a stable source for flow battery grade vanadium.

Queensland vanadium electrolyte plant investment also fits into a wider end to end supply chain vision. Vecco, Sumitomo Electric and Idemitsu Australia signed a 2024 agreement to develop and sell vanadium redox flow batteries. Therefore, vanadium units from Julia Creek could ultimately flow into installed energy storage systems across Australia.

Building a regional hub for vanadium redox flow batteries

Queensland is using the Queensland vanadium electrolyte plant investment to establish Townsville as a vanadium processing hub. Since 2021, the state has been developing a shared use vanadium processing facility to support smaller miners. This shared infrastructure should lower entry barriers and encourage more junior projects to progress.

At the same time, the Townsville electrolyte plant will target utility and industrial scale storage markets. Vanadium redox flow batteries offer long cycle life and deep discharge, which suit grid firming and renewable integration. However, they require secure supplies of high purity vanadium electrolyte to remain competitive with lithium ion systems.

Queensland’s support for Vecco, alongside Japanese partners, strengthens cross border industrial ties. It also diversifies vanadium production away from traditional suppliers in China, Russia and South Africa. As a result, the Queensland vanadium electrolyte plant investment could reshape regional vanadium trade and pricing dynamics over time.

The Metalnomist Commentary

This move shows how relatively modest public capital can unlock strategic value in long duration storage supply chains. By backing integrated mining and electrolyte production, Queensland improves the bankability of vanadium redox flow projects and attracts Japanese technology partners. Market participants should watch how fast offtake and project pipelines grow, as this will determine whether Townsville becomes a genuine Asia Pacific hub for vanadium battery materials.