Tailoring diffusion-induced stresses of core-shell nanotube electrodes in lithium-ion batteries

Carbon-coated electrode nanoparticles enhance the cycling stability of lithium-ion batteries due to their intrinsic electric conductivity and excellent tolerance to mechanical stress. To study diffusion-induced stresses of these nanocomposites, nanotube electrodes wrapped with carbon shells are investigated including the effects of surface stress. The results of our model show that diffusion-induced stresses strongly depend on the thickness of carbon layer, which should be tuned to endure material strengths, avoiding mechanical fracture. In addition, surface tension produces compressive stresses through the electrode materials, even a tensile state can turn into a state of compressive stress, which may become a resistance to brittle fracture.