QAZAQ GREEN.  Scientists from Tohoku University and Nitto Boseki Co., Ltd. have successfully created a novel electrode material that could enable the development of easily recyclable aqueous batteries, potentially contributing to decarbonization efforts, according to press release of the company.

The research team, led by Associate Professor Kouki Oka from Tohoku University's Institute of Multidisciplinary Research for Advanced Materials, overcame longstanding compatibility issues between organic electrode materials and water-based electrolytes by introducing p-dihydroxybenzene into a hydrophilic polyamine through a simple condensation reaction.

Aqueous batteries have existed for centuries and offer safety and cost advantages, but their use in modern energy storage applications like grid storage and electric vehicles has been limited due to material compatibility problems. Organic redox polymers, in particular, have faced barriers due to their hydrophobic nature and recycling challenges.

The newly developed polymer maintains high water compatibility and functions as an electrode-active material at room temperature (25°C). Crucially, it can be decomposed into raw components under mild conditions at temperatures below 100°C.

"This study provides a design strategy for making hydrophobic redox molecules compatible with aqueous systems," said Oka. "By combining high charge storage capacity with recyclability, we can open new directions for sustainable battery research."

The breakthrough offers two significant advantages: water-based electrolytes eliminate fire risks associated with conventional flammable solvents, and the polymers' composition from abundant elements and easy decomposition could reduce resource consumption and plastic pollution.

The team plans to evaluate durability and other performance factors to assess the material's potential for real-world applications.

The research was published online in Polymer Journal on August 26, 2025, and was selected for the special issue "Rising Stars in Polymer Science 2025." The study involved collaboration between Tohoku University's Graduate School of Engineering and Institute of Multidisciplinary Research for Advanced Materials, along with Nitto Boseki Co., Ltd.