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Ceramic Li1.3Al0.3Ti1.7(PO4)3 (LATP) with high ionic conductivity and stability in ambient atmosphere is considered to be potent as a solid-state electrolyte of solid-state lithium metal batteries (SSLMBs), but its huge interfacial impedance with electrodes and the unwanted Ti4+-mediated reduction reaction caused by the lithium (Li) metal anode greatly limit its application in LMBs. Herein, a composite polymer electrolyte (CPET) was integrated by in situ gelation of dual-permeable 1, 3-dioxolane (DOL) in the tandem framework composed of the commercial cellulose membrane TF4030 and a porous three-dimensional (3D) skeleton-structured LATP. The in situ gelled DOL anchored in the tandem framework ensured nice interfacial contact between the as-prepared CPET and electrodes. The introduction of the porous 3D LATP endowed CPET the increased lithium-ion migration number (tLi+ ) of 0.70, a wide electrochemical stability window (ESW) of 4.86 V, and a high ionic conductivity of 1.16 × 10–4 S cm–1 at room temperature (RT). Meanwhile, the side reaction of the LATP/Li metal was adequately restrained by inserting TF4030 between the porous LATP and Li anode. Profiting from the superb interfacial stability and the enhanced ionic transport capacity of CPET, Li/Li batteries based on the optimal CPET (CPET2) cycled over 2000 h at 20∼30 °C smoothly. Moreover, solid-state LiFePO4 (LFP)/Li with CPET2 exhibited excellent electrochemical performance with a capacity retention ratio of 72.2% after 400 cycles at 0.5C. This work offers an integrated strategy to guide the fabrication of a highly conductive solid electrolyte and a stable interface design for high-performance SSLMBs.

The NASICON-type inorganic electrolyte Li1.3Al0.3Ti1.7(PO4)3 (LATP) is an ideal solid electrolyte material for solid-state batteries due to its remarkable lithium-ion conductivity, wide electrochemical window, and superb environmental stability. However, its poor contact with electrodes and incompatibility with lithium (Li) anodes cause high interfacial impedance or even electrolyte deactivation. To address these issues, a double-side-modified LATP ceramic pellet with a flexible polyvinylidene fluoride (PVDF) polymer electrolyte capable of promoting LATP/electrode interfacial contact and synchronously modifying LATP/Li interfacial compatibility is constructed. The results demonstrate that the introduction of the PVDF buffer layers effectively reduces the interface impedance (5789 Ω → 271 Ω), prevents the occurrence of unwanted reactions of Li anode and LATP, and thus ensures the stable operation of the battery. The Li/Li cell fabricated by PVDF-modified LATP ceramic pellet exhibits over 3000 h of stable dendrite-free cycling at 0.1 mA cm–2 and small polarization (30 mV). This solid-state LiFePO4/Li battery exhibits a capacity retention of 83.4% after 300 cycles, implying its good cycling stability. This study indicates that such an interfacial modification strategy is effective for anodic protection and contributes to the formation of stable solid-state batteries.

In order to explore the effect of treadmill exercise on mitochondrial DNA damage and myocardial telomerase activity in aging model rats based on the classical apoptosis signaling pathway, a total of 36 clean-grade male SD rats are selected. After modeling, the rats are randomly divided into groups, namely, control and 3 times/w and 6 times/w exercise rats, with 12 rats in each group. After the rats of each group are modeled, the myocardial tissue and cells are collected, the apoptosis of myocardial cells is detected by TUNEL method, and the protein expressions of Bax and Bcl-2 in myocardial tissue are detected by western blotting. The mtDNA content of the control rats is the highest, which is significantly higher than that of the exercise group ( P < 0.05 ); the expression of mtDNA content in the heart of the rats exercising 3 times/w is significantly higher than that of the rats exercising 6 times/w ( P < 0.05 ); cardiomyocyte apoptosis AI value, Bcl-2, and Bax expressions of the control rats is the highest and significantly higher than those in the exercise group ( P < 0.05 ); Bcl-2/Bax in the control rats is the lowest and is significantly lower than that in the exercise group ( P < 0.05 ). The AI value, Bcl-2, and Bax expression of myocardial cell apoptosis in 3 times/w exercise rats are significantly higher than those in 6 times/w exercise rats ( P < 0.05 ); Bcl-2/Bax of 3 times/w exercise rats is significantly lower than that in 6 times/w exercise rats ( P < 0.05 ); by observing the rats that completed treadmill exercise, Akt2 protein of 3 times/w exercise rats and 6 times/w exercise rats is observed and analyzed. Compared with the control rats, the expressions of the two proteins are increased in 3 times/w exercise rats and 6 times/w exercise rats, and the upregulation in 6 times/w exercise rats is significantly increased and higher than that in 3 times/w exercise rats ( P < 0.05 ). For aging rats, treadmill exercise can reduce the body Bcl-2 and Bax values, improve the mitochondrial DNA damage and myocardial cell telomerase activity in aging model rats, and slow down the aging process.

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