Novel polyimide binder for achieving high-rate capability and long-term cycling stability of LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) cathode via constructing polar and micro-branched crosslinking network structure  

作　　者：Yueming Xu Yali Wang Nanxi Dong Chuanzhi Pu Bingxue Liu Guofeng Tian Shengli Qi Dezhen Wu 

机构地区：[1]State Key Laboratory of Chemical Resource Engineering,Beijing University of Chemical Technology,Beijing 100029,China [2]ENFI R&D Institute,China ENFI EngineeringCorporation,Beijing 100038,China [3]China Automotive Battery Research Institute Co.,Ltd.,Beijing 101407,China

出　　处：《Journal of Energy Chemistry》2023年第1期19-31,I0002,共14页能源化学（英文版）

基　　金：supported by the Fundamental Research Funds for the Central Universities(XK1802-2);the National Key Basic Research Program of China(973 Program,2014CB643604);the National Natural Science Foundation of China(51673017);National Natural Science Foundation of China(21404005);the Natural Science Foundation of Jiangsu Province(BK20150273)。

摘　　要：LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)material,as the promising cathode candidate for next-generation highenergy lithium-ion batteries,has gained considerable attention for extremely high theoretical capacity and low cost.Nevertheless,the intrinsic drawbacks of NCM811 such as unstable structure and inevitable interface side reaction result in severe capacity decay and thermal runaway.Herein,a novel polyimide(denoted as PI-Om DT)constructed with the highly polar and micro-branched crosslinking network is reported as a binder material for NCM811 cathode.The micro-branched crosslinking network is achieved by using 1,3,5-Tris(4-aminophenoxy)benzene(TAPOB)as a crosslinker via condensation reaction,which endows excellent mechanical properties and large free volume.Meanwhile,the massive polar carboxyl(-COOH)groups provide strong adhesion sites to active NCM811 particles.These functions of PIOm DT binder collaboratively benefit to forming the mechanically robust and homogeneous coating layer with rapid Li+diffusion on the surface of NCM811,significantly stabilizing the cathode structure,suppressing the detrimental interface side reaction and guaranteeing the shorter ion-diffusion and electron-transfer paths,consequently enhancing electrochemical performance.As compared to the NCM811 with PVDF binder,the NCM811 using PI-Om DT binder delivers a superior high-rate capacity(121.07 vs.145.38 m Ah g^(-1))at 5 C rate and maintains a higher capacity retention(80.38%vs.91.6%)after100 cycles at 2.5–4.3 V.Particularly,at the high-voltage conditions up to 4.5 and 4.7 V,the NCM811 with PI-Om DT binder still maintains the remarkable capacity retention of 88.86%and 72.5%after 100 cycles,respectively,paving the way for addressing the high-voltage operating stability of the NCM811 cathode.Moreover,the full-charged NCM811 cathode with PI-Om DT binder exhibits a significantly enhanced thermal stability,improving the safety performance of batteries.This work opens a new avenue for developing high-energy NCM811 based lithium-ion batteries

关 键 词：POLYIMIDE BINDER Micro-branched crosslinking network NCM811 cathode Lithium-ion battery 

分 类 号：TQ133.3[化学工程—无机化工] TM911.4[电气工程—电力电子与电力传动]