From agricultural waste to energy storage: Biomass carbon could advance potassium-ion batteries
A new review maps how renewable biomass can be transformed into high-performance battery anodes, while identifying the challenges that must be solved before large-scale commercialization
image: A critical review of biomass-derived carbon anodes for potassium-ion batteries
Credit: Yongfeng Zhu, Xiaowen Liu, Jinze Dai & Qingang Xiong
The rapid growth of electric vehicles, portable electronics, and renewable energy systems is increasing global demand for rechargeable batteries. Lithium-ion batteries currently dominate the market, but limited lithium resources and rising costs have intensified the search for affordable alternatives.
A new review published in Sustainable Carbon Materials highlights potassium-ion batteries as a promising option for future large-scale energy storage. The researchers report that carbon materials produced from agricultural residues and other forms of biomass could help overcome one of the major technical barriers facing potassium-ion batteries: the development of stable, high-performance anodes.
“Biomass-derived carbon combines renewable raw materials with structural features that are highly favorable for potassium storage,” said corresponding author Qingang Xiong of the South China University of Technology. “By understanding how pore structure, defects, graphitization, and surface chemistry affect battery performance, researchers can design better anodes and move potassium-ion technology closer to practical application.”
Potassium is considerably more abundant than lithium and can support batteries with competitive operating voltages and rapid ion transport. These characteristics make potassium-ion batteries especially attractive for stationary energy storage, where affordability, resource availability, and long service life are critical.
However, potassium ions are larger than lithium ions. Their size can cause slow reactions, substantial volume changes, and structural damage within conventional anodes during repeated charging and discharging. These effects reduce capacity and shorten battery life.
Biomass-derived carbon materials offer a potential solution. Their large surface areas, porous architectures, expanded carbon layers, and abundant structural defects can create additional sites for potassium storage while shortening the distance ions must travel.
The review evaluates several major categories of biomass-derived carbon anodes, including activated carbon, graphite-like carbon, carbon aerogels, hard carbon, carbon nanotubes, carbon dots, and carbon fibers.
These materials can be produced from resources such as corn husks, rice husks, tea waste, soybeans, cellulose, distilled grain residues, and animal hide. Some reported materials have demonstrated strong cycling stability. For example, graphite-like carbon produced from tea waste retained 94 percent of its capacity after 1,000 cycles, while carbon nanotube materials prepared from distilled grain residues retained 94 percent after 600 cycles.
No single material currently satisfies every practical requirement. Activated carbon can provide extensive potassium-storage surfaces but may suffer from limited cycling performance. Hard carbon offers structural stability but often has low initial efficiency. Carbon aerogels and nanotubes can deliver attractive properties, although complex processing, high costs, and limited production remain obstacles.
The authors also compare pyrolysis, hydrothermal treatment, and microwave-assisted carbonization, together with physical and chemical activation methods. The selected production route strongly determines pore structure, surface chemistry, energy consumption, material yield, and electrochemical performance.
Future priorities include heteroatom doping to improve electronic properties, balancing potassium adsorption and intercalation to limit volume expansion, and using pre-potassiation to improve initial efficiency. Researchers must also simplify the production of carbon aerogels, identify abundant precursors for nanotubes, and improve the porosity and graphitization of carbon fibers.
The review concludes that scalable, energy-efficient, and precisely controlled manufacturing will be essential for converting low-cost biomass into commercially relevant battery materials. By linking renewable feedstocks with next-generation energy storage, biomass-derived carbon could support both waste utilization and reduced dependence on lithium resources.
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Journal reference: Zhu Y, Liu X, Dai J, Xiong Q. 2026. A critical review of biomass-derived carbon anodes for potassium-ion batteries. Sustainable Carbon Materials 2: e022 doi: 10.48130/scm-0026-0017
https://www.maxapress.com/article/doi/10.48130/scm-0026-0017
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About Sustainable Carbon Materials:
Sustainable Carbon Materials (e-ISSN 3070-3557) is a multidisciplinary platform for communicating advances in fundamental and applied research on carbon-based materials. It is dedicated to serving as an innovative, efficient and professional platform for researchers in the field of carbon materials around the world to deliver findings from this rapidly expanding field of science. It is a peer-reviewed, open-access journal that publishes review, original research, invited review, rapid report, perspective, commentary and correspondence papers.