Research on interface engineering of solid-state lithium battery -Lithium - Ion Battery Equipment
Traditional lithium 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 problems. However, due to the low electrical conductivity between solid-state particles, the electrical conductivity in solid-state batteries has been unsatisfactory until the report on the use of MOF as the framework host and the lithium ion liquid as the ion transport guest (MOF-IL). Batteries open up new research perspectives. Recently, the team of Prof. Pan Feng from the School of Advanced Materials, Shenzhen Graduate School of Peking University, 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 "Enhancedlithiumdendritesuppressingcapabilityenabledbyasolid-like electrolytewithdifferent-sized nanoparticles" (Chem.Commun.,2018,54,13060-13063;natureindex journal DOI:10.1039/c8cc07476c), and was recommended as a cover article highlighted.(Lithium - Ion Battery Equipment)
The team investigated the effect of particle size on the performance of MOF-IL ionic conductors in metallic lithium batteries. The researchers used a combination of two ionic conductors with different particle sizes. Compared with a single-component ionic conductor, the mixed size can effectively reduce the voids between the electrolyte particles and create new contact points between the electrolyte particles and the electrolyte and lithium metal surfaces. , so that the lithium deposition is more uniform, and thus the ability to hinder the growth of lithium dendrites is improved. And due to the newly added ion channel, the conductivity of the electrolyte is also improved to a certain extent. This kind of solid electrolyte and commercial cathode materials LiFePO4, LiCoO2 and anode material lithium metal assembled into batteries also showed considerable rate performance and cycle performance. The initial capacity of LiCoO2|electrolyte|Li battery was 129mAhg-1, and after 100 cycles 94.6% retention rate; LiFePO4|electrolyte|Li battery has an initial capacity of 137mAhg-1 and a 94.8% retention rate after 100 cycles.
This work was completed by Wang Ke, a 2017 graduate student, under the joint guidance of Professor Pan Feng and Dr. Yang Luyi from the School of Advanced Materials. 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.JCYJ20160531141048950and JCYJ20151015162256516).