The team of Professor Pan Feng from Peking University: About the Ru0026D progress of solid-state lithium battery interface engineering

: Lithium-ion batteries, as a clean energy with a wide range of research and applications, are widely used in cutting-edge technology fields such as daily electronic products, artificial intelligence, electric vehicles, and drones. However, with the rapid development of lithium-ion batteries, their safety performance has become more and more of people's most concern. Traditional lithium-ion batteries use liquid electrolytes, and the properties of the liquid electrolytes directly affect their safety performance. Solid-state lithium batteries can solve some of the safety issues. However, due to the low electrical conductivity between solid particles, the electrical conductivity in solid-state batteries has been unsatisfactory. The battery opens up new research perspectives. Recently, the team of Professor Pan Feng, School of New Materials, Peking University Shenzhen Graduate School, based on this perspective, further improved the safety performance and ion transport performance of this type of solid electrolyte. The research results were recently published in Chemical Communications, entitled 'Enhanced lithium dendrites uppressing capability enabled by a solid-like electrolyte with different-sized nanoparticles' (Chem. Commun., 2018, 54, 13060-13063; nature index DOI: 10.1039/c8cc07476c), and was recommended as a cover article highlight. The team studied the effect of particle size in metal lithium batteries on the performance of MOF-IL ion conductors. The researchers combined two ion conductors with different particle sizes. Compared with a single-component ion conductor, the mixed size can effectively reduce the gap between the electrolyte particles and increase the contact points between the electrolyte particles and the surface of the electrolyte and the lithium metal. The lithium deposition is made more uniform, and thus the ability to inhibit the growth of lithium dendrites is improved. And due to the increase of ion-conducting channels, the conductivity of the electrolyte is also improved to a certain extent. This type of solid electrolyte and commercial cathode materials LiFePO4, LiCoO2 and anode material lithium metal assembled into a battery also showed considerable rate performance and cycle performance. The initial capacity of LiCoO2|electrolyte|Li battery is 129mAhg-1. The retention rate of 94.6%; the initial capacity of LiFePO4|electrolyte|Li battery is 137mAhg-1, and the retention rate is 94.8% after 100 cycles. Under the joint guidance of Professor Pan Feng and Dr. Yang Luyi of the School of New Materials, the work was completed by Wang Ke, a graduate student of 2017. The above work was supported by the National Material Genome Major Project (2016YFB0700600), the National Natural Science Foundation of China (Nos.21603007), and the Shenzhen Science and Technology Innovation Commission (Nos.JCYJ20160531141048950andJCYJ20151015162256516).