With many reported attempts on fabricating single-ion conducting polymer electrolytes, they still suffer from low ionic conductivity, narrow voltage window, and high cost. Herein, we report an unprecedented approach on improving the cationic transport number (t Li +) of the polymer electrolyte, i.e., single-ion conducting polymeric protective interlayer (SIPPI), which is designed between the conventional polymer electrolyte (PVEC) and Li-metal electrode. Satisfied ionic conductivity (1 mS cm–1, 30 °C), high t Li + (0.79), and wide-area voltage stability are realized by coupling the SIPPI with the PVEC electrolyte. Benefiting from this unique design, the Li symmetrical cell with the SIPPI shows stable cycling over 6000 h at 3 mA cm–2, and the full cell with the SIPPI exhibits stable cycling performance with a capacity retention of 86% over 1000 cycles at 1 C and 25 °C. This incorporated SIPPI on the Li anode presents an alternative strategy for enabling high-energy density, long cycling lifetime, and safe and cost-effective solid-state batteries.

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With high ionic conductivity and good contact/adhesion with electrodes, quasi-solid polymer electrolyte (QPE) is considered as one of the most promising options to address the safety concerns of next-generation rechargeable...

Lithium (Li) metal is a highly promising anode material for next-generation high-energy-density batteries, while Li dendrite growth and the unstable solid electrolyte interphase layer inhibit its commercialization. Herein, a chemically grafted hybrid dynamic network (CHDN) is rationally designed and synthesized by the 4,4′thiobisbenzenamine cross-linked poly(poly(ethylene glycol) methyl ether methacrylate-r-glycidyl methacrylate) and (3-glycidyloxypropyl) trimethoxysilane-functionalized SiO 2 nanoparticles, which is utilized as a protective layer and hybrid solid-state electrolyte (HSE) for stable Limetal batteries. The presence of a dynamic exchangeable disulfide affords self-heability and recyclability, and the chemical attachment between SiO 2 nanoparticles and the polymer matrix enables the homogeneous distribution of inorganic fillers and mechanical robustness. With integrated flexibility, fast segmental dynamics, and autonomous adaptability, the as-prepared CHDN-based protective layer enables superior electrochemical performance in half cells and full cells (capacity retention of 83.7% over 400 cycles for the CHDN@Li/LiFePO 4 cell at 1 C). Furthermore, benefiting from intimate electrode/electrolyte interfacial contact, CHDN-based solid-state cells deliver excellent electrochemical performance (capacity retention of 89.5% over 500 cycles for the Li/HSE/LiFePO 4 cell at 0.5 C). In addition, the Li/HSE/LiFePO 4 pouch cell exhibits superior safety, even exposing various physical damage conditions. This work thereby provides a fresh insight into a rational design principle for dynamic network-based protective layers and solid-state electrolytes for battery applications.

Taking the potential risk of water and mud inrush in the construction of a water conveyance tunnel of a hydropower station as the engineering background, based on the field investigation and data collection, the whole process of tunnel construction is simulated and analyzed by using 3D finite element Midas. The results show that because the tunnel passes through the strong water rich fault fracture zone, the filling material in the fault fracture zone has obvious stress concentration under the coupling action of high stress, high pressure seepage and construction disturbance, and the displacement of the filling material has increased significantly. After the fault fracture zone is exposed, the seepage speed has increased significantly, indicating that water and mud inrush disaster has occurred here. It is suggested that when the tunnel passes through complex water-rich fault, monitoring and early warning and excavation support measures should be strengthened to prevent water and mud inrush accidents. The research results have a certain guiding role for the safe construction of the tunnel project.

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A water conveyance tunnel of a hydropower station encountered the disaster of water inrush and mud inrush in the fault fracture zone, which caused the filling collapse in the fault fracture zone on the face of the tunnel, which seriously threatened the safety construction of the workers and affected the construction period. Based on the comprehensive analysis of the influencing factors of water and mud inrush in the fault fracture zone of the tunnel, this paper makes a preliminary analysis of the water and mud inrush in the tunnel, and puts forward the comprehensive treatment measures for the construction of the collapse section. Through the field engineering practice, this disposal measures passed the collapse section smoothly. The research results can be used for reference to the cause analysis of water and mud inrush in the fault fracture zone of similar tunnels and the construction method in the collapse section.