The C/C–SiC composites were fabricated by the liquid silicon infiltration method. The mechanical and tribological properties of C/C–SiC composites were assessed and compared based on different C/C densities and the carbon fiber textile architecture. The results demonstrated that the bending and shear strengths of C/C–SiC were lower than those of C/C composites, which resulted from the carbon fibers being corroded during the process of infiltration of liquid silicon. In contrast to C/C composites, the compressive strength of C/C–SiC exhibited higher values due to the presence of SiC ceramics. Moreover, the mechanical strength of C/C composites increased gradually with the increase of the C/C preform density. The tribological properties of various C/C–SiC composites showed a stable friction phase at an intermediate braking stage. When the density of C/C preforms was around 1.78 g/cm ³ , the C/C–SiC composites exhibited excellent friction coefficients (0.438 and 0.465), and low wear rates (linear and weight wear rates were 0.450 µm/time and 0.123 g/cycle, respectively). Furthermore, the C/C–SiC composites fabricated with non-woven carbon fiber needling preforms showed relatively a higher friction value and wear rate than those of C/C–SiC with PANOF integral C/C preforms. Therefore, C/C–SiC composites have been considered promising friction materials for braking system applications.

The mechanical behavior of electrode composite during the drying preparation has played a crucial role in the electrochemical performance of lithium-ion batteries (LIBs). Our work aimed at developing an integrated analysis method to study the component distribution, mechanical properties, and internal stress of composite coating in the process of electrode drying. The main influence factors of drying stress were thoroughly investigated. It was found that this present model could capture not only the heterogeneity effect of inactive ingredients but also the porosity-dependent viscoelasticity of electrode composite. Meanwhile, the calculated effective modulus and stress evolution upon drying time were in acceptable accord with the experimental data. Furthermore, the rapid solidification markedly increased the drying stress in electrodes and significantly impaired the tensile strength of electrode composite due to the highly gradient distributed constituents. However, the stress level at high drying temperature could be significantly reduced by an aqueous sodium alginate binder instead of poly(vinylidene fluoride). The obtained results will be a great help in efficiently manufacturing LIB electrodes with adequate mechanical integrity.

In this paper, the cracking of the solid electrolyte (SE) and its impacts on the effective Li-ion conductivity of composite electrodes of all-solid-state lithium-ion batteries (ASSLIBs) are investigated numerically. A two-dimensional finite element (2D FEM) model was developed for composite electrodes in which active material particles (AM particles) are embedded in the solid electrolyte. The 2D FEM model can successfully calculate and simulate the diffusion-induced stress, the generation of solid electrolyte cracks (SE cracks), and the Li-ion transport. The degradation of Li-ion conductivity for cracked composite electrodes is calculated with the homogenization method. It is revealed that the diffusion-induced volume variation in AM particles can generate significant stress and thus SE cracking in composite electrodes of ASSLIBs. The calculated results suggest that swelling AM particles are more favorable than shrinking AM particles for the structural stability of composite electrodes. It is also demonstrated that the evolution of the conductivity with the propagation of SE cracking is consistent with the percolation theory. The fundamental understating of the SE cracking and its impact in this paper may benefit the design of novel ASSLIBs with more stable performance and a longer lifespan.

An electro-chemo-mechanical model is developed for lithium-ion battery (LIB) considering the damage of active material (AM) particles. The established model is used to evaluate the effect of stress and the effect of damage on the electro-chemo-mechanical behavior of cathode. The cathode is generated with a random distribution method. Computational results show that moderate stress is beneficial for the battery performance, while damage generated by high stress can considerably degrade the battery capacity. The impact of several structural factors on the electro-chemo-mechanical behaviors of LIB are investigated. Smaller particles are found beneficial for the battery performance. Furthermore, the computational results also suggest that an increasing particle size from the separator to the current collector leads to higher capacity. The presented model helps to understand the electro-chemo-mechanical coupling mechanism of LIB.