Australian scientists have proven that liquid solvent-free solid-state batteries can be easily made, paving the way for a future free from batteries catching fire or exploding if they become too hot.
Research fellows at Deakin University’s Institute for Frontier Materials, Dr Fangfang Chen and Dr Xiaoen Wang, say their discovery means that lithium-ion batteries found in items such as mobile phones, computers and vehicles would no longer pose a fire risk because the highly volatile liquid electrolyte currently used in them would be replaced with a solid polymer material.
“This investigation has the potential to underpin some very significant work to improve batteries at two key points,” Dr Wang said.
“Our findings suggest that next-generation batteries will be much safer and have exceptionally better performance. From what we’ve discovered, this electrolyte will allow us to use a lithium metal anode, which could see future batteries last twice as long as they currently do with one charge. Alternatively, batteries could end up half of their size and weight without compromising performance time.”
Dr Chen believes that the findings could change the way batteries are handled in everyday life too.
“If industry implements our findings, I see a future where battery reliant devices can be safely packed in aeroplane baggage, for example, or where electric cars don’t pose a fire risk for occupants or emergency services like they currently do,” Dr Chen said.
Current lithium-ion batteries are highly flammable and the predominant cause of fires in battery reliant product.
“We’ve reinvented the way polymer interacts with lithium salt, removing the normally highly flammable properties of traditional lithium batteries,” Dr Chen stated.
The researchers say they’ve used existing commercial polymer materials to create the new process, meaning that the formulation could be applied commercially with little difficulty.
Dr Wang said that all of the products that they’ve used to make this safer battery process already exist in the market.
“Polymers have been used as battery conductors for over 50 years, but we’re the first to use existing commercial polymer in an improved way.”
“We’ve done this by weakly bonding the lithium-ion with polymer, creating solid polymer electrolytes. We believe this is the first clear and useful example of liquid-free and efficient transportation of lithium-ion in the scientific community.”
The process has already been proven in coin cell batteries, similar to a watch battery size, with the next step being to scale up the batteries to bigger applications – such as for a mobile phone.
“We have started the pouch cell fabrication and testing at Deakin’s word-class Battery Technology Research and Innovation Hub at Waurn Ponds. Once we achieve pouch size, we hope to attract collaboration with industry partners,” Dr Wang concluded.
‘Poly(Ionic Liquid)s-in-Salt-Electrolytes with Coordination-Assisted Lithium-Ion Transport for Safe Batteries’ was recently published in the journal Joule.