SoftBank to Produce Large-Scale Batteries for AI Data Centers in Japan

SoftBank Corp. announced plans to begin large-scale production of battery cells and energy storage systems at its plant in Sakai, Osaka Prefecture, to meet rising electricity demand from artificial intelligence services. The telecommunications unit of SoftBank Group will partner with South Korea-based battery company Cosmos Lab and AI firm DeltaX Co.

to enable mass production starting in the fiscal year that begins next April. The initial target is output at a scale of 1 gigawatt hour per year, which would rank it among the largest such facilities in Japan. The company said the batteries will primarily help power the AI data centers it is developing.

They will also be supplied for grid stabilization, factories and other industrial and residential uses. Over the medium term, SoftBank Corp. intends to expand sales into global markets. Bloomberg reported last month that the company could eventually scale capacity to several gigawatt hours.

The partnership with Cosmos Lab and DeltaX Co. was disclosed in a company statement on Monday. Production is set to commence in April 2027 under the fiscal calendar used by many Japanese firms. SoftBank Corp. has not detailed the exact financial terms of the collaboration or the specific technology each partner will contribute.

The statement emphasized the need to address growing power requirements driven by AI computing demands.

Demand for energy storage has increased as technology companies build out data centers capable of running advanced AI models. Battery systems can provide backup power and help balance electricity loads on the grid during peak usage. Converting or expanding it for battery manufacturing represents a diversification beyond traditional telecommunications infrastructure.

The company did not disclose projected investment costs or expected job creation at the site. BloombergNEF data cited in reports indicates that a 1 GWh annual capacity would place the plant among Japan's leading battery production sites.

While initial output focuses on the domestic market, SoftBank Corp. signaled ambitions to serve international customers in coming years. It did not specify target regions or timelines for overseas sales. The announcement comes as governments and companies worldwide invest heavily in both AI development and the supporting energy infrastructure.

Reliable, large-scale storage is viewed as essential to sustaining continuous operation of data centers. >"SoftBank Corp. " — SoftBank Corp. statement, May 11, 2026 (Japan Times) No timeline was given for when the first batteries would be deployed in SoftBank's own data centers or sold externally.

The company has previously outlined ambitions to become a major player in AI-related infrastructure.