Nanosheet cellulose-assisted solution processing of highly conductive and high loading thick electrode for lithium-ion batteries

Thick electrode technology has attracted much attention of the industry as an effective and practical way to achieve high energy density of batteries, since it just needs to increase the mass loading of electrode per unit area with no changes in battery system. However, with the increase of the thickness and the mass loading of the electrode, the electrode films are more susceptible to cracking due to stress concentration. Besides, the ionic conductivity and electronic conductivity inside the electrode decrease significantly. Herein, we propose a nanosheet cellulose-assisted solution processing of highly conductive and high loading thick electrode for lithium-ion battery. With the help of two-dimensional celluloses that possess high surface area, rich functional groups and outstanding mechanical properties, we can homogenize the distribution of conductive agents and construct a robust network to wrap the active materials, so that the LiCoO2 thick electrode obtained can achieve a high mass loading of 50 mg cm−2 and a capacity retention rate six times higher than that of the dry electrode after 50 cycles.