Metal-air Battery Market

The global metal-air battery market size was USD 0.68 Billion in 2025 and is expected to register a revenue CAGR of 33.5% during the forecast period. Market revenue growth is supported by accelerating demand for multi-day, long-duration grid storage as renewable penetration rises past the four-hour discharge window that dominant lithium-ion battery energy storage systems are typically sized for. Form Energy, the largest disclosed iron-air battery developer, closed a USD 750 million Series G financing round in August 2026 led by T. Rowe Price, raising its equity value above USD 2 billion, and has more than 75 GWh of commercial iron-air projects under agreement, including a 300 MW / 30 GWh system announced with Xcel Energy in February 2026, the largest battery system by energy capacity announced globally at the time. Canadian zinc-air developer e-Zinc separately raised more than USD 50 million in Series A2 financing in September 2025, backed by Toyota, Mitsubishi Heavy Industries and Evok Innovations. These are some of the key factors driving revenue growth of the market.

Iron-air multi-day storage developers, zinc-air long-duration storage developers, and aluminum-air backup power and range-extension developers are the commercial categories that constitute the metal-air battery market, with grid operators, utilities and, increasingly, artificial intelligence data center operators the primary customers for the technology's signature advantage of low-cost, multi-day discharge duration unmatched by lithium-ion chemistries. For instance, in March 2026, Form Energy, USA, announced an agreement with Crusoe to supply 12 gigawatt-hours of iron-air batteries for artificial intelligence data center power infrastructure, manufactured at the company's Form Factory 1 facility in Weirton, West Virginia, illustrating how AI-driven electricity demand growth is converting directly into metal-air battery procurement alongside traditional utility customers.

However, metal-air chemistries remain constrained by fundamentally lower round-trip efficiency and power density than lithium-ion batteries, making them suited to multi-day and seasonal discharge applications rather than the fast-response, high-power use cases that dominate today's grid-scale battery market. Manufacturing capacity also remains nascent relative to disclosed contract volume: Form Energy's Weirton facility was designed to ramp toward roughly 500 megawatts of annual capacity by 2028, a fraction of the more than 75 GWh of commercial projects the company has under agreement, and the technology's few other developers, including e-Zinc, Zinc8 Energy Solutions and Phinergy, remain at pilot or early-commercial production scale. These factors substantially limit metal-air battery market growth over the forecast period.

Based on technology, the global metal-air battery market is segmented into iron-air, zinc-air, aluminum-air, and lithium-air and other emerging chemistries. The iron-air segment commands the largest revenue share because Form Energy has raised more capital, disclosed more contracted project volume and reached commercial-scale manufacturing further ahead of every other metal-air developer, with its iron-air technology's reversible rusting electrochemistry offering roughly 10,000 Wh per litre of theoretical volumetric capacity at raw material cost far below lithium, cobalt or nickel, according to academic benchmarking of metal-air chemistries.

The zinc-air segment is expected to register a rapid revenue growth rate in the global metal-air battery market over the forecast period, from a small 2025 base. e-Zinc's USD 50 million-plus Series A2 round in September 2025, backed by Toyota Ventures, Mitsubishi Heavy Industries, Export Development Canada and Ultratech Capital Partners, will fund pilot-to-commercial manufacturing scale-up for its modular zinc-air system, which forms zinc pellets during charging and dissolves them during discharge, while Zinc8 Energy Solutions continues to advance its own zinc-air platform for long-duration renewable integration applications.

• 01What is the global metal-air battery market size in 2025 and what CAGR is expected during 2026-2035?
• 02How much did Form Energy raise in its August 2026 Series G financing round, and what is the company's resulting equity value?
• 03What agreement did Form Energy sign with Crusoe in March 2026, and what customer segment does it represent for iron-air batteries?
• 04What 300 MW / 30 GWh system did Form Energy announce with Xcel Energy in February 2026?
• 05How much did e-Zinc raise in its September 2025 Series A2 round, and which investors participated?
• 06Why does the iron-air segment account for the largest technology revenue share in the global metal-air battery market?
• 07What partnership has Phinergy formed with Indian Oil Corporation, and what stake does IOC hold in the company?
• 08Why does the zinc-air segment register the fastest revenue growth rate in the global metal-air battery market over the forecast period?
• 09What manufacturing capacity is Form Energy's Weirton, West Virginia facility targeting by 2028, and how does it compare with the company's contracted project volume?
• 10What theoretical volumetric capacity advantage do iron-air batteries offer relative to lithium-air systems, according to academic benchmarking?

This report covers the global metal-air battery market across all major segments and geographic regions. Primary research combines panel conversations with industry experts and is cross-referenced against company annual reports and government agency data. All market size figures use 2025 as the base year with a 2026-2035 forecast period.