An analytical multiscale modeling of a nanocomposite anode with graphene nanosheets for lithium-ion battery

An analytical calculation of diffusion-induced stress in a layered electrode composed of a current collector and a nanocomposite active plate for lithium-ion batteries is proposed. The active plate of the bilayer nanocomposite anode is reinforced by graphene nanosheets (GNSs), whose mechanical properties are predicted by the Mori–Tanaka micromechanical method. The reinforced GNSs will make agglomeration in the matrix, which has a certain obstacle to reducing the overall stress level of the anode. The size effect of a single GNS also affects the corresponding material properties, and the Halpin–Tsai equation can be used to acquire the reliable prediction results. The analytical solutions of the diffusion-induced stress and strain of the nanocomposite anode under galvanostatic charging operation are derived, and then, the elastoplastic stress distribution in the interior of the anode is obtained. In addition, the effect of GNS’s thickness on the migration of the plastic interface is also evaluated.