New Electrolyte Additive Could Boost Performance Of Zinc-Ion Batteries
Scientists have developed a new electrolyte additive that could significantly improve the durability, safety and affordability of rechargeable zinc-ion batteries, potentially accelerating their adoption in renewable energy storage and grid-scale applications.
Aqueous zinc-ion batteries (AZIBs) have attracted growing interest as a low-cost, safe and environmentally sustainable alternative to lithium-ion batteries. However, their commercial deployment has remained limited due to persistent challenges such as zinc dendrite formation, hydrogen evolution reactions, corrosion and poor long-term cycling stability.
Researchers from the Institute of Nano Science and Technology (INST), Mohali, an autonomous institute under the Department of Science and Technology (DST), have now developed a novel electrolyte additive designed to address these issues through interface engineering rather than costly material redesign.
Tackling Key Challenges In Zinc-Ion Batteries
The newly developed additive, known as 1,3-bis (1,3-dicarboxypropyl)-1H-imidazole-3-ium chloride (BDIM), selectively adsorbs onto zinc metal surfaces and regulates the Inner Helmholtz Plane (IHP), a critical region where electrochemical reactions occur within aqueous zinc-ion batteries.
To create BDIM, researchers dissolved glutamic acid in sodium hydroxide and water before adding glyoxal, formaldehyde and acetic acid. The mixture was heated at 70°C under nitrogen for 24 hours and later processed to obtain a crystalline powder.
The additive contains multiple oxygen and nitrogen donor sites that strongly interact with zinc metal. During battery operation, BDIM preferentially occupies the Inner Helmholtz Plane on the negatively polarised zinc surface.
As a result, water molecules are displaced from the interface, reducing unwanted side reactions that typically degrade battery performance.
Suppressing Corrosion And Dendrite Formation
One of the most significant advantages of the additive is its ability to suppress hydrogen evolution, corrosion and zinc dendrite growth.
Dendrites are needle-like metal structures that can form during charging and discharging cycles, often leading to reduced battery life and safety concerns. By regulating the interface between the electrolyte and the zinc electrode, BDIM helps maintain a more stable electrochemical environment.
Consequently, the battery experiences less performance degradation over time, leading to improved cycling stability and longer operational life.
The approach offers a practical and scalable solution for extending battery lifespan without increasing manufacturing complexity or costs.
Advanced Techniques Reveal Zinc Deposition Mechanisms
To gain deeper insights into how the additive functions, researchers combined a laboratory-developed ultramicroelectrode (UME) with fast-scan cyclic voltammetry (FSCV).
The ultramicroelectrode, measuring less than 50 micrometres, alters diffusion behaviour from linear to radial or hemispherical due to its extremely small size. This characteristic enables high scan-rate measurements and more detailed observations of electrochemical processes.
Meanwhile, FSCV allowed scientists to monitor changes in charge-transfer behaviour after introducing the additive. Together, the techniques provided direct information about interfacial charge-transfer and mass-transfer kinetics, helping researchers better understand zinc deposition mechanisms.
These findings offer valuable insights into the fundamental processes governing zinc battery performance.
Potential Applications In Renewable Energy Storage
The research was led by Dr Ramendra Sundar Dey, Scientist E at INST Mohali, and has been published in the ACS Electrochemistry journal.
According to the researchers, the technology has potential applications across aqueous zinc-ion batteries, renewable energy storage systems, backup power solutions and grid-scale energy infrastructure.
By improving battery longevity and reducing degradation, the additive could lower maintenance costs and enhance the reliability of energy storage systems. Furthermore, safer and longer-lasting zinc-ion batteries may provide an attractive alternative for large-scale storage of renewable energy generated from sources such as solar and wind power.
The development represents an important step towards creating cost-effective and sustainable battery technologies capable of supporting the growing global demand for clean energy storage.
With inputs from PIB