Nanoscale Structure of Positive Electrodes for Lithium-Ion Batteries with Graphene-Based Additives According to Small-Angle Neutron Scattering

In this paper, we continue the adaptation of neutron-scattering methods for studying the microstructure of electrode materials of lithium-ion batteries in order to improve their specific energy storage. The effect of conductive carbon additives (graphene and graphene oxide) on the porous structure of electrodes with various bases, including LiFePO 4 , Li 4 Ti 5 O 12 , and LiNiMnCoO 2 , is studied via the small-angle scattering of thermal neutrons. To separate the scattering by closed and open pores, the electrodes are wetted with a typical liquid electrolyte with a deuterated liquid carrier (dimethyl carbonate), which leads to the matching of scattering by open pores. It is established that electrically conductive carbon additives change the porosity of the electrode to varying degrees and affect the wettability of materials due to both varying degrees of penetration into the pores of the initial material and the effect on the initial matrix. A universal effect on the dispersion of a polymer binder (polyvinylidene fluoride) is also found.