A Chinese startup, 中科荣熠 (Zhongke Rongyi), presented an all-solid-state iron-air battery at the World Laureates Forum Future Energy Conference, held alongside the anniversary of the journal Watt, on 31 October 2026. The company was founded in 2025 and has a team of about 21 people recruited starting in March 2026.
A solid ceramic electrolyte instead of aqueous liquid
Unlike Form Energy in the United States and Ore Energy in the Netherlands, which use aqueous liquid electrolytes, Zhongke Rongyi uses a solid ceramic electrolyte. The company says this avoids hydrogen-evolution side reactions and the need for flammable organic electrolytes. Its small-area cells have reportedly exceeded performance thresholds in testing, although the work remains at an early stage.
The differentiator is the electrolyte: a solid ceramic replaces the aqueous liquid used by Form Energy and Ore Energy.
From a thorium reactor programme to iron-air
The technology traces back to the 2011 CAS Strategic Priority Research Program (Class A) on a thorium molten-salt reactor nuclear energy system, carried out in cooperation with the Shanghai Institute of Applied Physics (CAS), where iron-air batteries served as storage support for nuclear systems. The team selected the iron-air route in 2015, validated a dual-electrolyte molten-salt system in 2018, advanced a semi-solid molten-salt system in 2021, and then moved to an all-solid-state design.
Cost targets and target markets
According to the company's business plan, initial investment cost can be controlled at 0.5–0.6 RMB/Wh, with a levelized cost of storage of around 0.1 RMB/Wh. Zhongke Rongyi argues the route can be cost-competitive with lithium-ion for durations above four hours, with the unit-cost advantage growing as duration increases because the active material is iron.
Target markets are nuclear storage (described as the base market), wind and solar co-located storage, grid peak shaving, and AI data centers.
The company expects China's main demand to remain concentrated at four to eight hours for a considerable period. A National Energy Administration report shows that, as of end-2025, new-type energy storage with four-hour-plus duration accounted for 27.5% of installed capacity, up 12.1 percentage points year on year.
Iron-air chemistry itself is not new: the battery stores and releases energy through the reversible oxidation, or "rusting", of iron, discharging as iron oxidizes and charging by reducing iron oxide back to iron. The open question for the solid-state variant is whether ceramic electrolytes can be manufactured at scale and survive repeated cycling — the gap between small-area cells and commercial modules.
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