Flowing zinc slurry battery points to low-cost long-duration energy storage
Fudan University and CAS researchers report a flowing zinc slurry battery with 99.94% Coulombic efficiency and 5,128 hours of operation in Nature Energy.
Photo by Sergei Starostin on Pexels
Researchers at Fudan University and the Chinese Academy of Sciences have demonstrated a flowing zinc slurry battery that ran reversibly for 5,128 hours under continuous flow, a design aimed at low-cost long-duration energy storage for renewable power. The study, “Flowing zinc slurry for long-duration energy storage”, was published in Nature Energy on June 24, 2026, and drew wider press coverage in mid-July.
The team, led by corresponding author Fei Wang of Fudan University in Shanghai, reports a Coulombic efficiency of 99.94% in asymmetric test cells – a measure of how much charge the battery returns compared with what it takes in. Full cells paired with a manganese dioxide electrode retained 81.1% of their capacity after 5,500 cycles.
How the zinc slurry battery works
In the zinc slurry battery, nanoscale zinc particles are dispersed in a conductive network and pumped through the cell, where they undergo reversible zinc/Zn2+ redox conversion. A ligand-assisted confinement strategy coordinates onto the surfaces of the zinc nanoparticles, suppressing excessive zinc growth and parasitic reactions and enabling uniform, monodisperse zinc deposition throughout the slurry, according to the paper’s abstract. This addresses the poor reversibility that has held back aqueous zinc batteries.
“The major advantage of this design is that it transforms Zn from a static electrode into a dynamic energy carrier,” Wang stated, as reported by Interesting Engineering on July 17, 2026. Wang said the concept was inspired by a zinc electrowinning plant, where Zn2+ ions are converted into metallic zinc.
| Test configuration | Result |
|---|---|
| FZS-Cu asymmetric cell, 8 mA per cm2 | 99.94% Coulombic efficiency |
| Symmetric cell, 22.5 mA per cm2, 135 mAh per cm2, continuous flow | 5,128 hours of reversible operation |
| FZS-MnO2 full cell, 10 A per g | 81.1% capacity retention after 5,500 cycles |
| FZS-O2 full cell, 1.35 mA per cm2 | 1.65 Ah delivered over 100 hours |
Source: abstract of “Flowing zinc slurry for long-duration energy storage”, Nature Energy, June 24, 2026. FZS = flowing zinc slurry.
Why decoupling energy from power matters for grid storage
Like other flow batteries, the flowing architecture separates energy storage capacity from power delivery: capacity can be scaled by adding more slurry in external tanks, without redesigning the cell itself. That makes the approach a candidate for storing intermittent solar and wind power over long durations and releasing it when generation falls, the researchers state. Zinc is cheaper and more abundant than the vanadium used in commercial flow batteries or the lithium in conventional battery packs, although the paper does not publish a direct cost comparison in its abstract.
The work adds a new option to a widening field of long-duration storage chemistries. Other contenders include iron-air technology, examined in Are iron-air batteries the key to long-duration storage?, and sodium-ion cells such as the Rept Battero 320 Ah sodium-ion storage cell unveiled earlier in 2026.
Background
Aqueous zinc batteries have long been studied as a safe, water-based and low-cost alternative to lithium-ion for stationary storage, but poor reversibility of the zinc electrode has limited their lifetime. The Nature Energy paper, received in May 2025 and accepted in May 2026, applies the flow-battery principle to zinc itself: instead of a static zinc electrode, the metal circulates as a slurry of nanoparticles. Nature Energy published an accompanying Research Briefing, “Ligand-confined zinc slurries enable durable flow-based energy storage”, on July 13, 2026. The authors acknowledge the Dalian Institute of Chemical Physics of the Chinese Academy of Sciences for a large-area slurry flow-battery demonstration, an early step from laboratory cells towards the scale grid storage would require.
Sources: Nature Energy; Nature Energy Research Briefing; Interesting Engineering
Featured image: photo by Budget Bizar on Pexels (free Pexels license).
Become a Sponsor
Our website is the heart of the mission of WINSS – it’s where we share updates, publish research, highlight community impact, and connect with supporters around the world. To keep this essential platform running, updated, and accessible, we rely on the generosity of you, who believe in our work.
We offer the option to sponsor monthly, or just once choosing the amount of your choice. If you run a company, please contact us via info@winssolutions.org.
I specialize in sustainability education, curriculum co-creation, and early-stage project strategy. At WINSS, I craft articles on sustainability, transformative AI, and related topics. When I’m not writing, you’ll find me chasing the perfect sushi roll, exploring cities around the globe, or unwinding with my dog Puffy — the world’s most loyal sidekick.
