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The mining of non-coal mines is a fundamental industry in China and an important pillar of economic development. It plays an increasingly important role in the development of many emerging industries. With the increasing intensity of mineral resource development, many typical safety production accidents occurred in the non-coal mining industry. To explore the main safety issues of non-coal mines in China, I collected safety production data of non-coal mines during the 13th Five Year Plan period (2016-2020) and analyzed separately from accident area, accident type, accident occurrence time, mining method, mining type, industry, etc. The results are as follows; 1)Small and medium-sized non-coal mines in China have caused over 90% of accidents with a production capacity of about 40%,and the safety production foundation is weak; 2)The security production situation in key regions such as Inner Mongolia, Hunan, and Guangxi is severe; 3)The number and death toll of accidents in underground mines account for over 50% of the total number of accidents in non-coal mines, with the 10 types of accidents mainly involving roof fall and collapse resulting in a higher number of fatalities. The main reasons for this situation are that the safety management capabilities of non-coal mining enterprises are still weak, the safety production supervision capabilities of non-coal mining enterprises need to be improved, the intelligent construction of non-coal mines in China is still in the initial stage, and the overall level of mechanization, automation, and intelligent construction in accident stricken areas is relatively low. Only the equipment Intelligence level of non-coal mining enterprises and regulatory authorities was improved, and all production processes and links throughout the entire lifecycle of the mine were upgraded and transformed, the further improvement of safety production quality during the 14th Five Year Plan period can only be achieved. [ABSTRACT FROM AUTHOR]

The interphase structure and Li-ion transport across the interface are essential for high-performance composite solid electrolytes (CPEs). Tailoring the interface between rigid inorganic solid electrolyte fillers and the polymer electrolyte matrix is a promising way. A Li-ion conductive filler such as garnet Li7La3Zr2O12 (LLZO) is proposed for the high performance of CPEs, which suffered from an unavoidable insulating contamination layer and incomplete contact with the polymer matrix. In this study, a wet chemical method was applied for converting the insulation layer on the LLZO surface to LiF with the formation of oxygen vacancies by NH4F solution etching at moderate temperature. The equally dispersed in situ formed LiF in CPEs improves the electrochemical stability. Removal of resistive barriers accompanied by firm contact with the polymer matrix induced by bonding between PEO chains and oxygen vacancies forms a CPE with homogeneous fast Li-ion transport. Owing to these advantageous properties, the ionic conductivity of CPEs with etched LLZO increases from 6.45 × 10−4 S cm−1 to 1.28 × 10−3 S cm−1 at 60 °C, and the electrochemical stable window is extended. An all-solid-state battery with etched powder exhibits extraordinary cycle stability at 2C with an initial discharge capacity of 136 mA h g−1, and capacity retention remains at 90.4% after 300 cycles. [ABSTRACT FROM AUTHOR]