Converting low-cost industrial polymer into zinc-ion battery cathodes

Academics from the Flinders University of South Australia and Griffith University have published findings into the potential of aqueous zinc-ion batteries [AZIBs] as a more sustainable energy storage technology alternative to lithium-ion batteries.

Published in a September 2024 issue of the Energy Storage Materials journal, the research paper is titled “Converting a low-cost industrial polymer into organic cathodes for high mass-loading aqueous zinc-ion batteries.”

Zhongfan Jia, lead for the Jia Research Group at Flinders and college of science and engineering associate professor in chemistry and nanotech researcher, said AZIBs could have real-world applications from electric vehicles to portable electronic devices, as polymer AZIBs using organic cathodes are low-cost, simple to produce, and potentially biodegradable.

AZIBs can also address the supply-chain issues of strategic metals, including lithium and cobalt, availability and the cost of spent batteries needing to be recycled.

A comparison of battery performance for AZIBs using PTEMPO-3 as the cathode, 2 M Zn(ClO4)2 as the electrolyte, and different carbons as conductive additives (a) MWCNTs, (b) N234, (c) BP2000, and (d) YP-50F. Battery configuration: PTEMPO-3/carbon=1/1 (w/w). *Image: Flinders University*

“AZIBs stand out because of the much higher abundance of zinc in the Earth’s crust (ten times more than lithium), and their low toxicity and high safety,” Jia said.

AZIBs usually use zinc metal as an anode and inorganic or organic compounds as a cathode. While substantial work has been devoted to improving the stability of zinc anodes, high-performing cathodes are needed and remain a major challenge.

“Our research is building conductivity using nitroxide radical polymer cathodes made from cheap commercial polymer and optimizing the battery performance using low-cost additives,” Jia said.

“The work re-evaluates the use of high redox potential nitroxide radical polymers cathodes in AZIBs and produced the highest mass loading so far.”

An AZIB with a capacity of 60 mAh easily powered a small electric fan and model car during the research. *Image: Flinders University*

The study is led by Flinders masters student Nanduni Gamage and postdoc fellow Dr Yanlin Shi, who have developed a lab-made pouch battery using scaled-up polymer (at an approximate cost of AUD 20 ($13.61)/kg), a non-fluoro Zn(ClO4)2 electrolyte, and BP 2000 carbon black (AUD 1/kg) without binder to provide a capacity of nearly 70 mAh g-1 and a middle discharge voltage of 1.4 V.

With a mass loading of 50 mg/cm-², the pouch battery had a capacity of 60 mAh, which easily powered a small electric fan and a model car.

Collaborators in the study included Jesús Santos-Peña, from the Université Paris Est Creteil CNRS, in France, who worked with other experts from the Flinders University Institute for Nanoscale Science and Technology.

From left, Jia Lab researchers Yanlin Shi, Nanduni Gamage, and PhD candidate Chanaka Mudugamuwa with the novel pouch battery they developed. *Image: Flinders University*

The team has also reecently developed organic radical/K dual-ion batteries, a technique that can also relieve dependence on lithium-ion devices.

The research is being supported by Australian Research Council, the French-Australian International Research Network on Conversion and Energy Storage funding, and the Australian National Fabrication Facility’s South Australia node for supporting the electroanalytical and electrochemical synthesis labs at Flinders University.

From pv magazine Australia.