title: A systematic investigation of polymer binder flexibility on the electrode performance of lithium-ion batteries.
abstract: The mechanical failure at the electrode interfaces (laminate/current collector and binder/particle interfaces) leads to particle isolation and delamination, which has been regarded as one of the main reasons for the capacity decay and cell failure of lithium-ion batteries (LIBs). Polymer binder provides the key function for a good interface property and for maintaining the electrode integrity of LIBs. Triethylene glycol monomethyl ether (TEG) moieties were incorporated into polymethacrylic acid (PMAA) to different extents at the molecular level. Microscratch tests of the graphite electrodes based on these binders indicate that the electrode is more flexible with 5 or 10% TEG in the polymer binders. Crack generation is inhibited by the flexible TEG-containing binder, compared to that of the unmodified PMAA-based electrode, leading to the better cycling performance of the flexible electrode. With a 10% TEG moiety in the binder, the graphite half-cell reaches a reversible capacity of >270 mAh/g at the 1C rate, compared to a value of ∼190 mAh/g for the unmodified PMAA binder.
authors.affiliation: Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
authors.forename: Neslihan
authors.initials: N
authors.lastname: Yuca
authors.forename: Hui
authors.initials: H
authors.lastname: Zhao
authors.forename: Xiangyun
authors.initials: X
authors.lastname: Song
authors.forename: Murat Ferhat
authors.initials: MF
authors.lastname: Dogdu
authors.forename: Wen
authors.initials: W
authors.lastname: Yuan
authors.forename: Yanbao
authors.initials: Y
authors.lastname: Fu
authors.forename: Vincent S
authors.initials: VS
authors.lastname: Battaglia
authors.forename: Xingcheng
authors.initials: X
authors.lastname: Xiao
authors.forename: Gao
authors.initials: G
authors.lastname: Liu
keywords: flexibility; graphite anode; lithium-ion battery; polymer binder