Clarification of the dispersion mechanism of cathode slurry of lithium-ion battery under effects of both poly vinylidene fluoride/carbon black ratio and mixing time  

作　　者：Zhilong Wang Zhenzhen Zhao Ye Yang An Zhang Xiayi Liu Tong Zhao Yahui Cui 

机构地区：[1]School of Mechanical and Precision Instrument Engineering,Xi'an University of Technology,Xi'an 710048,China

出　　处：《Particuology》2024年第5期116-127,共12页颗粒学报（英文版）

基　　金：support from National Natural Science Foundation of China(grant No.52006176 and 62101438);the Key Research and Development Project of Shaanxi Province(grant No.2022kw-18);the Ministry of Education's“Chunhui Plan”Collaborative Research project(grant No.202200491);Science and Technology Program of Xi'an(grant No.22GXFW0095)。

摘　　要：This paper presents the effects of both poly vinylidene fluoride(PVDF)/carbon black(CB)ratio(m PVDF:m CB)and mixing time t on the dispersion mechanism of the cathode slurry of lithium-ion battery(LIB).The dispersion mechanism is deduced from the electrochemical,morphological and rheological properties of the cathode slurry by using electrical impedance spectroscopy(EIS),scanning electron microscopy and rheology methods,respectively.From the perspective of EIS method,static simulation models are established in the COMSOL Multiphysics software;meanwhile,the simulated results are used to verify the correctness of the electrochemical properties of the cathode slurry.As a result,the following conclusions are able to be obtained.Firstly,in the case of the mass ratio m_(PVDF):m_(CB)=5:10,LiCoO_(2) particles are completely coated by the mixture of CB and PVDF to form a stable polymer gel structure.Higher or lower m_(PVDF):m_(CB) leads to the larger impedance and worse dispersion status for the cathode slurry.Secondly,when t=6 min,a good gel-like conductive network structure is formed by coating the thinner evenly dispersed CB–PVDF double layer around LiCoO_(2) particles.Finally,a strategy regarding to both m_(PVDF):m_(CB) and t in experimental scale is proposed,which has the capability of improving the performance of LIB.

关 键 词：Cathode slurry Dispersion mechanism Lithium-ion battery(LIB) 

分 类 号：TM912[电气工程—电力电子与电力传动]