Italian energy storage developer Green Energy Storage (GES) has unveiled a high-density manganese-hydrogen hybrid battery designed to store renewable power over long periods, a move that could reshape grid-scale energy storage economics.
At an event in Rovereto, Trento, officials and industry partners highlighted the new system, which combines a manganese-based electrolyte with hydrogen gas in a hybrid flow cell architecture.
The design allows energy to be stored for many hours or days, addressing limitations of traditional lithium-ion systems used for short-duration loads.
The heart of the technology is its hybrid gas-liquid flow configuration, which separates the chemical reactions that store and release energy.
During charging, electricity splits water molecules to generate hydrogen gas and changes the oxidation state of the manganese electrolyte.
When energy is needed, the hydrogen recombines with the charged electrolyte to release electricity.
Long-Duration Storage for Renewables
The system is aimed at long-duration energy storage (LDES) markets where solar and wind power integration requires storing surplus generation over multi-hour or multi-day periods.
Conventional lithium-ion batteries, widely used today, are optimized for short cycles lasting hours, not days.
Energy efficiency for the system is reported at more than 75 percent, and it is engineered for a service lifecycle exceeding 10,000 cycles, which analysts say implies decades of field use if commercialized at grid scale.
GES’s chief executive has told industry media the battery’s levelized cost of storage (LCOS) could fall to about €0.02 per kilowatt-hour per cycle, well below costs typical of lithium-ion and other long-duration solutions.
Prototype and Commercial Rollout
The company, backed by Europe’s Important Projects of Common European Interest (IPCEI) funding and a strategic agreement with engineering firm RINA, plans to unveil its first prototype in December 2025.
GES says it intends to begin commercial deployment by 2027, with initial installations likely in industrial facilities and renewable plants requiring flexible storage capacity.
Italy’s regional government for Trento, which hosted the launch event, said the project aligns with local and national energy transition strategies to bolster renewables and reduce dependence on imported energy technologies.
Industry Context
Experts say grid operators and utilities are increasingly seeking storage solutions that go beyond lithium-ion because of cost, material supply chain risks and the need to manage longer variations in wind and solar output.
GES’s use of manganese, an abundant and low-critical material, aims to reduce reliance on metals like cobalt and nickel that are concentrated in select global markets.
The company also emphasizes circular economy principles and recyclability in its design.
