Fangzhou Zhang

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.

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 lithium–fluorinated carbon (Li/CF_x) battery possesses the highest energy density (2180 Wh kg⁻¹) among all the primary lithium batteries. However, the poor electronic conductivity of the fluorinated carbon (CF_x) material sets a limit on its rate discharge capability, confining its practical application. In this article, a doping strategy at a mild anneal condition is developed to synthesize the phosphorus species‐doped CF_x materials (P‐CF_x) for Li/CF_x batteries. Compared to the commonly used methods, this eco‐friendly, and simple doping method does not involve washing, centrifugation, and filtration processes. Characterization using X‐Ray diffraction, high‐resolution transmission electron microscope, and X‐Ray photoelectron spectroscopy confirms the successful doping and the structure of the P‐CF_x. Density functional theory calculations and characterization results demonstrate that phosphorus species doping can alter microstructure and induce charge redistribution to improve electronic and ionic conductivity. Therefore, the Li/P‐CF_x battery possesses a high specific capacity and an excellent rate capability, shown by a high discharge capacity of 810 mAh g⁻¹ with a voltage plateau of 2.53 V at 0.1 C. Extraordinarily, a discharge capacity of 597 mAh g⁻¹ with a voltage plateau of 1.90 V at 20 C has been achieved as well as a high power density of 34 048 W kg⁻¹.

Lung squamous cell carcinoma (LUSC) is a disease with high morbidity and mortality. Many studies have shown that aberrant alternative splicing (AS) can lead to tumorigenesis, and splicing factors (SFs) serve as an important function during AS. In this research, we propose an analysis method based on synergy to screen key factors that regulate the initiation and progression of LUSC. We first screened alternative splicing events (ASEs) associated with survival in LUSC patients by bivariate Cox regression analysis. Then an association network consisting of OS-ASEs, SFs, and their targeting relationship was constructed to identify key SFs. Finally, 10 key SFs were selected in terms of degree centrality. The validation on TCGA and cross-platform GEO datasets showed that some SFs were significantly differentially expressed in cancer and paracancer tissues, and some of them were associated with prognosis, indicating that our method is valid and accurate. It is expected that our method would be applied to a wide range of research fields and provide new insights in the future.

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.

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.

This paper presents a study on the variation of compressive failure mechanisms in carbon fiber reinforced polymer (CFRP) as well as the effects of material properties and structure parameters on the compressive strength in different failure mechanisms. A two-dimensional microscale model is developed to simulate numerically the compressive process of CFRP with local structure imperfections. The fiber kinking can be induced by either the interfacial failure or the matrix yielding depending on the interfacial strength of carbon fibers. CFRP with lower interfacial strength can exhibit wider kink band. Higher Young’s modulus of matrix, yield strength of matrix or misalignment level causes the failure mechanisms variation to occur at higher interfacial strengths, while the fiber diameter affects the failure mechanism variation in the opposite way. Furthermore, the compressive strength is found to be sensitive to the variation of matrix properties in the matrix-driven failure and to the fiber diameter in the interface-driven failure. These findings indicate that the strategies for the compressive strength enhancement can be different according to the compressive failure mechanisms.