A new type of electrochemically active lithium battery cathode material has been developed!

Recently, Tang Yongbing, a researcher at the Functional Thin Film Materials Research Center of the Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, and his team members, and a Lightfoot Professor Sun Chenghua from the University of St Andrews in the United Kingdom, a professor at Swinburne University of Technology in Australia, and a professor at Tsinghua University, Berkeley, Shenzhen Researcher Cheng Huiming successfully developed a new type of lithium ion battery cathode material with dual anion and cation electrochemical activity. This work has important reference significance for the research of new energy storage devices and related materials based on multiple electrochemical reaction active centers. Related research results of oxalate cathodes for lithium-ion batteries with cation and polyanion redox combination ('cationic and polyanionic redox active lithium oxalate battery cathode materials') have been published online in'Nature Communications' 2019, DOI) on: 10.1038 / s41467-019-11077-0). With the rapid development of key industries such as portable electronic devices, electric passenger tools, and energy storage, lithium-ion batteries have been forced to have higher performance indicators. However, just like the barrel effect, the disadvantage of lithium-ion battery performance lies in the positive electrode. Therefore, the design and development of cathode materials is the current research focus. Traditional cathode materials for lithium-ion batteries mainly include oxides and polyanions. Among them, oxide cathodes such as lithium cobalt oxide have two redox pairs of transition metal and oxygen anion, so the capacity is relatively high. However, the electrochemical reaction of the oxygen anion is unstable, and it is easy to generate gas and cause the cathode structure to collapse, which leads to battery failure and serious safety accidents. The polyanion positive electrode (such as lithium iron phosphate) significantly improves the structural stability of the material due to the polyanion as the structural framework, but the polyanion as an inactive component reduces the total energy density. Therefore, if a new cathode material can be developed, the advantages of the two reaction mechanisms can be effectively combined, and it is expected that high safety and high energy density can be achieved. Based on the above considerations, Tang Yongbing and his team members Yao Wenjiao, Zhou Xiaolong and others successfully developed a new type of Li2Fe(C2O4)2 polyanionic cathode material in the United Nations international team, and found that the polyanionic cathode material has iron ion and oxalate base for the first time. The two electrochemical activities of the cluster. The reversibility of Fe2 + / Fe3 + changes has been verified by Mössbauer spectroscopy and the fine structure of the near absorption side and extended absorption side of the in-situ synchrotron; in-situ Raman spectroscopy and the near-side absorption side structure verification of the carbon-oxygen synchrotron radiation give The reversible change of the oxalate anion group is shown; further theoretical calculations give the electrochemical reaction mechanism of the new cathode material. The research discovered a new type of polyanionic cathode material with dual electrochemical activity of anion and cation, which has important guiding significance for the research and development of secondary battery cathode materials based on multiple electrochemical active centers. Disclaimer: The articles published on this site are all from the Internet and do not represent the views of this site. If there is any infringement, please contact to delete WeChat: Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact delete A: Does the new national standard for electric vehicles make management more standardized? The insider told the truth~