Scientists at the Institute of Nano Science and Technology (INST), Mohali, have developed a novel electrolyte additive that could significantly improve the performance, safety and lifespan of aqueous zinc-ion batteries (AZIBs), paving the way for more cost-effective and sustainable energy storage solutions.
AZIBs are increasingly being viewed as a safer and cheaper alternative to lithium-ion batteries due to their low cost, environmental sustainability and inherent safety. However, their widespread adoption has been limited by challenges such as zinc dendrite growth, hydrogen evolution reactions (HER), corrosion and poor cycling stability.
To address these issues, researchers focused on interface engineering rather than expensive material redesign. Their study highlights a practical and scalable approach to enhancing battery durability while maintaining affordability, a key requirement for large-scale renewable energy storage applications.
The research team, led by Dr Ramendra Sundar Dey, Scientist E at INST, developed an electrolyte additive known as 1,3-bis(1,3-dicarboxypropyl)-1H-imidazole-3-ium chloride (BDIM). The findings have been published in the journal ACS Electrochemistry.
The additive was synthesised by dissolving glutamic acid in sodium hydroxide and water, followed by the addition of glyoxal, formaldehyde and acetic acid. The mixture was heated at 70°C under a nitrogen atmosphere for 24 hours before being extracted and lyophilised to obtain crystalline BDIM powder.
According to the researchers, BDIM contains multiple oxygen and nitrogen donor sites that strongly interact with zinc metal. During battery operation, the additive selectively adsorbs onto the negatively polarised zinc surface and occupies the Inner Helmholtz Plane (IHP) — the region where electrochemical reactions occur.
By displacing water molecules from the interface, BDIM suppresses water-induced side reactions, including hydrogen evolution, corrosion and zinc dendrite formation. This helps improve battery stability and extends operational life.
To better understand zinc deposition mechanisms, the researchers combined a laboratory-developed ultramicroelectrode (UME) with fast-scan cyclic voltammetry (FSCV). The UME, measuring less than 50 micrometres, alters diffusion behaviour from linear to radial, enabling high scan rates, while FSCV allows scientists to observe changes in charge-transfer behaviour when additives are introduced.
The advanced analytical approach provided new insights into interfacial charge-transfer and mass-transfer kinetics, helping researchers better understand and control zinc deposition processes.
The technology has potential applications in aqueous zinc-ion batteries, renewable energy storage systems, backup power solutions and grid-scale energy storage infrastructure.
Researchers said the innovation could contribute to the development of safer, longer-lasting and more affordable rechargeable batteries. By improving battery lifespan and reducing performance degradation, the technology could lower maintenance costs and enhance the reliability of sustainable energy systems, supporting the broader transition to clean energy.
