Researchers have developed a new generation of lithium metal batteries which can offer extended lifespan and more safety at elevated temperatures.
The research team was led by Professor Dong-Myeong Shin of Department of Mechanical Engineering at the University of Hong Kong (HKU).
The lithium metal battery innovation is focused on microcrack-free polymer electrolytes.
The lithium metal battery innovation
Batteries have become an essential part of everyday lives, however the ones which are in use today use liquid electrolytes and carbonaceous anodes.
Moreover, they also have other drawbacks such as safety concerns, short lifespan, and inadequate power density.
Further, there is a need to have batteries which can operate at extreme temperatures – to meet industrial sector requirements, and for other specific jobs.
This requirements has led researchers to look for solid electrolytes that are fit for use with lithium metal anodes. The lithium metal anodes are known for their high theoretical specific power capacity.
The microcrack-free polymer electrolytes developed by Professor Shin’s team are synthesized via a straightforward one-step click reaction, exhibiting notable attributes including resistance to dendrite growth and non-flammability, demonstrating a high electrochemical stability window up to 5 V, and an ionic conductivity of 3.1 × 10−5 S cm−1 at high temperatures.
These enhancements are attributed to tethered borate anions within the microcrack-free membranes, which facilitate accelerated selective transport of Li+ ions and suppress dendrite formation, according to a release by the University of Hong Kong.
Polymer membranes play a key role in enhancing performance
The release further mentions that these anionic network polymer membranes enable lithium metal batteries to function as safe, long-cycling energy storage devices at high temperatures, maintaining 92.7% capacity retention and averaging 99.867% coulombic efficiency over 450 cycles at 100°C.
Normally, the cycling performance of conventional liquid electrolytes Li metal batteries is fewer than 10 cycles at high temperatures.
The breakthrough potentially paves the way for future advancements in anionic polymer electrolyte design for next-generation lithium batteries.
“We believe this innovation opens doors for new battery chemistries that can revolutionize rechargeable batteries for high-temperature applications, emphasizing safety and longevity,” said Dr Jingyi Gao, the first author of the paper.
Apart from applications in high-temperature scenarios, the microcrack-free electrolyte membranes also have the potential to enable fast charging due to low overpotential. This capability could allow electric vehicles to recharge in the time it takes to drink a cup of coffee, marking a significant advancement towards a clean energy future,” Professor Shin added.
The findings have been published in the journal Advanced Science.
