SoftBank is moving into battery production in Japan to respond to rapidly rising power demand driven by the spread of artificial intelligence. Its strategy is to build AI data centres and energy storage systems together and expand into a power and data infrastructure company.

Japan’s ITmedia reported on May 11 that SoftBank said it plans to build a battery production hub called the GX Factory on the former site of Sharp’s Sakai plant in Sakai, Osaka.

The project is linked to SoftBank’s Osaka Sakai AI data centre plan. The company plans to reorganise the site around three pillars: an AI data centre, an AX Factory responsible for manufacturing AI infrastructure, and a GX Factory for battery production. It aims to broaden its position beyond a telecoms operator into a power and data infrastructure company for the AI era.

The core is next-generation battery technology. SoftBank will work with South Korean company Cosmos Lab to develop a zinc halide battery that uses halides for the cathode and zinc for the anode. Unlike conventional lithium-ion batteries, it uses a freshwater-based electrolyte instead of a flammable organic electrolyte. SoftBank explained that this could structurally reduce the fire risk of lithium-ion batteries while securing similar or higher energy efficiency.

The parts procurement structure also has significance from a supply-chain perspective. It expects to strengthen its supply chain because it can source many key materials in Japan. The plan is to produce batteries stably at home for large power-demand users such as AI data centres.

Energy storage system development will be carried out jointly with DeltaX. SoftBank plans to apply a Cell-to-Pack structure that builds cells directly into packs without separate modules, reducing the number of parts and installation space. The company said it achieved an energy density of 5.37 MWh per standard container-type ESS unit through this technology, and claimed this is at a world-leading level.

An AI-based energy management system will also be applied to battery operations. SoftBank plans to use AI technology accumulated in its power business to forecast power demand and optimise charging and discharging. It explained that this would enable efficient power operations in line with changes in renewable energy generation.

Initial battery supplies will go to its own large AI data centres. It then plans to expand supply sequentially to grid, industrial and household uses. In the medium term, it is also keeping an entry into global markets in mind. SoftBank set a goal of achieving annual revenue of at least 100 billion yen by 2030 through the battery business.

The industry is paying attention to the point that the Sakai site is changing into a complex base that combines AI computing, power storage and infrastructure manufacturing, going beyond a simple data centre complex. With power demand surging in the AI era, the analysis is that SoftBank is moving to strengthen its infrastructure competitiveness by securing its own batteries and data centres at the same time.