Researchers from the University of Waterloo and GMâ€™s Global Research and Development Center have developed a new silicon-based anode material that they say could enable batteries with almost 10 times more energy density than todayâ€™s state of the art.
In â€œEvidence of covalent synergy in siliconâ€“sulfurâ€“graphene yielding highly efficient and long-life lithium-ion batteries,â€ published in Nature Communications, the team reports that the new electrode material shows superior reversible capacity, high coulombic efficiency, and high aerial capacity.
â€œGraphite has long been used to build the negative electrodes in lithium-ion batteries,â€ said Professor Zhongwei Chen, leader of the Waterloo team. â€œBut as batteries improve, graphite is slowly becoming a performance bottleneck because of the limited amount of energy that it can store.â€
Silicon is a strong candidate to replace graphite, but it tends to undergo significant expansion and contraction with each charge cycle, which causes the material to crack. To overcome this problem, Professor Chenâ€™s team developed a flash heat treatment for fabricated silicon-based lithium-ion electrodes that minimizes volume expansion.
â€œThe economical flash heat treatment creates uniquely structured silicon anode materials that deliver extended cycle life to more than 2,000 cycles with increased energy capacity of the battery,â€ said Professor Chen.
Chen plans to commercialize this technology, and expects to see new batteries on the market within the next year.