Fragmented Carbon Nanotube Macrofilms as Adhesive Conductors for Lithium-Ion Batteries

Polymer binders such as poly(vinylidene fluoride) (PVDF) and conductive additives such as carbon black (CB) are indispensable components for manufacturing battery electrodes in addition to active materials. The concept of adhesive conductors employing fragmented carbon nanotube macrofilms (FCNTs) is demonstrated by constructing composite electrodes with a typical active material, LiMn2O4. The adhesive FCNT conductors provide not only a high electrical conductivity but also a strong adhesive force, functioning simultaneously as both the conductive additives and the binder materials for lithium-ion batteries. Such composite electrodes exhibit superior high-rate and retention capabilities compared to the electrodes using a conventional binder (PVDF) and a conductive additive (CB). An in situ tribology method combining wear track imaging and force measurement is employed to evaluate the adhesion strength of the adhesive FCNT conductors. The adhesive FCNT conductors exhibit higher adhesion strength than PVDF. ...