SoftBank Pursues Lithium-Free Batteries for Data Centers

SoftBank Bets on Alternative Battery Chemistry

SoftBank is pushing to develop data center batteries that eliminate the need for lithium and cobalt — 2 of the most supply-constrained and geopolitically sensitive materials in the energy storage industry. The move signals a strategic shift as the Japanese conglomerate deepens its commitment to AI infrastructure while attempting to sidestep critical mineral bottlenecks.

The initiative comes at a time when global demand for data center capacity is surging, driven by the explosive growth of AI workloads. Traditional lithium-ion batteries, long the standard for backup power systems, face mounting pressure from rising material costs and ethical sourcing concerns tied to cobalt mining.

Why Data Centers Need a Battery Rethink

AI data centers consume staggering amounts of electricity. Every facility requires robust backup power to prevent costly outages. Currently, most rely on lithium-ion battery systems — the same technology powering electric vehicles and smartphones.

But the math is becoming problematic. Key challenges include:

• Lithium supply constraints: Global lithium prices have been volatile, and demand from EVs already strains supply chains
• Cobalt sourcing concerns: Roughly 70% of the world's cobalt comes from the Democratic Republic of Congo, where mining practices raise serious human rights issues
• Scaling limitations: The sheer number of planned AI data centers worldwide could overwhelm existing battery supply chains within years
• Fire safety risks: Lithium-ion batteries carry thermal runaway risks, a growing concern for dense data center environments
• Cost escalation: Material costs for lithium-ion systems have made large-scale deployment increasingly expensive

SoftBank's approach aims to address all of these pain points simultaneously.

Alternative Chemistries Gaining Traction

Several alternative battery technologies are emerging as viable candidates for data center applications. These include sodium-ion, iron-air, and zinc-based chemistries, all of which use abundant, low-cost materials.

Sodium-ion batteries, in particular, have attracted significant attention. Sodium is roughly 1,000 times more abundant than lithium in the Earth's crust, and the technology has matured rapidly over the past 2 years. Companies like CATL and BYD in China have already begun commercializing sodium-ion cells.

Iron-air batteries, championed by U.S. startup Form Energy, offer another promising path. They use iron — one of the cheapest and most plentiful metals on the planet — and can provide long-duration energy storage at a fraction of lithium-ion costs.

SoftBank's Broader AI Infrastructure Play

This battery initiative does not exist in isolation. SoftBank, led by CEO Masayoshi Son, has been making aggressive moves across the AI value chain. The company has committed tens of billions of dollars to AI infrastructure through various partnerships and investments.

Notable recent moves include:

• A reported $100 billion commitment to U.S. AI infrastructure as part of the Stargate project alongside OpenAI and Oracle
• Investments in Arm Holdings, whose chip designs power a growing share of data center processors
• Exploration of nuclear and renewable energy sources to power future AI facilities

Developing proprietary or preferred battery technology fits neatly into this strategy. Controlling the energy storage layer reduces dependency on external suppliers and could provide a competitive advantage as data center operators scramble for reliable power solutions.

What This Means for the Industry

SoftBank's push into lithium-free batteries could accelerate a broader industry shift. If successful, it would demonstrate that critical mineral dependency is not an inevitable cost of building AI infrastructure.

For Western data center operators like Microsoft, Google, and Amazon, the implications are significant. These companies collectively plan to spend over $200 billion on data center capital expenditure in the coming years. Alternative battery technologies could meaningfully reduce both costs and supply chain risks.

The environmental angle also matters. ESG-conscious investors and regulators are increasingly scrutinizing the material sourcing behind tech infrastructure. Batteries free of conflict minerals and environmentally destructive mining practices offer a cleaner narrative.

Challenges and Timeline Uncertainty

Despite the promise, significant hurdles remain. Alternative battery chemistries generally offer lower energy density than lithium-ion, meaning they require more physical space — a premium commodity in data center design.

Performance longevity is another open question. Data center batteries must deliver reliable backup power over 10 to 15 years with minimal degradation. Newer chemistries have not yet proven themselves over those timeframes in real-world deployments.

Manufacturing scale also presents a challenge. Building new battery supply chains from scratch takes years and billions in capital investment. SoftBank has deep pockets, but execution risk remains substantial.

Looking Ahead

SoftBank's bet on lithium-free data center batteries reflects a growing recognition that AI infrastructure cannot scale sustainably on the same materials that power today's consumer electronics and EVs. The competition for lithium and cobalt is only intensifying.

If SoftBank can deliver a cost-effective, scalable alternative, it could reshape how the entire industry approaches data center power resilience. The next 12 to 24 months will be critical in determining whether this vision moves from ambition to reality.