Solid-state lithium metal batteries with solid electrolytes are promising for next-generation energy-storage devices. However, it remains challenging to develop solid electrolytes that are both mechanically robust and strong against external mechanical load, due to the brittleness of ceramic electrolytes and the softness of polymer electrolytes. Herein, we propose a nacre-inspired design of ceramic/polymer solid composite electrolytes with the "brick-and-mortar" microstructure. The nacre-like ceramic/polymer electrolyte (NCPE) simultaneously possesses a much higher fracture strain (1.1%) than pure ceramic electrolytes (0.13%) and a much larger ultimate flexural strength (7.8 GPa) than pure polymer electrolytes (20 MPa). The electrochemical performance of NCPE is also much better than pure ceramic or polymer electrolytes, especially under mechanical load. A 5 × 5 cm 2 pouch cell with LAGP/poly(ether−acrylate) (PEA) NCPE exhibits stable cycling with a capacity retention of 95.6% over 100 cycles at room temperature, even undergoes a large This article is protected by copyright. All rights reserved. point load of 10 N. In contrast, cells based on pure ceramic and pure polymer electrolyte show poor cycle life. The NCPE provides a new design for solid composite electrolyte and opens up new possibilities for future solid-state lithium metal batteries and structural energy storage. The rapid-growing demands for portable electronics and electric vehicles have bolstered needs for next-generation lithium batteries with high energy density [1-4]. However, lithium batteries become more thermally vulnerable as energy density increases. Thermal runaway and explosion are prone to be triggered by failures such as mechanical damage and lithium dendrite growth inside batteries [5, 6]. Nonflammable solid-state ceramic electrolytes (SSEs) provide alternatives to conventional flammable liquid electrolytes [7-9]. Various ceramic electrolytes with attractive ionic conductivities have been developed in the past two decades, including NASICON-type Li 1.5 Al 0.5 Ge 1.5 (PO 4) 3 (LAGP) [10] , Li 1.3 Al 0.3 Ti 1.7 (PO 4) 3 (LATP) [11, 12] , garnet Li 7 La 3 Zr 2 O 12 (LLZO) [13, 14] , and sulfides, such as This article is protected by copyright. All rights reserved. NCPEs, polymer electrolytes and ceramic electrolytes were cut with a thickness of 500 μm and a size of 1.5 cm. A loading rate of 0.5 mm min-1 and a support span of 1.5 cm were used in all tests. The results were averaged from those in five similar specimens. The flexural stress is and The flexural strain is , where F, L, w, h, and D are the applied point force, span length, sample width, thickness, and flexural deflection, respectively. Vickers indentation was carried out on SANS-UTM 6000 using a Vickers indenter. Finite Element Mechanical Simulation: 2D nonlinear finite element simulations were conducted using the software ABAQUS v6.14. In these simulations, the stress/strain distributions and crack propagation in a regular brick-mortar structure and a ceramic film are calculate...

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Consumption of black tea contributed to many health benefits including the prevention of heart disease and certain types of cancer. However, the chemical composition of black tea has not been fully explored. Most studies have examined different interactions between the four major tea catechins, and limited studies have investigated the interaction between catechins and other components in tea. In the present study, we tested our hypothesis that the ortho-dihydroxyl structure of chlorogenic acid (CGA) could react with the vic-trihydroxy structure of (-)-epigallocatechin 3-gallate (EGCG) and (-)-epigallocatechin (EGC) to generate theaflavin-type of compounds during black tea fermentation. The reaction between CGA and EGCG or EGC was catalyzed by horseradish peroxidase (POD) in the presence of HO. Two theaflavin-type compounds EGCG-CGA and EGC-CGA were purified using a Sephadex LH-20 column. Their structures were elucidated on the basis of the analysis of their MS and 1D- and 2D-NMR spectroscopic data. Furthermore, the existence of these two novel compounds was characterized by LC/MS/MS analysis. We also found that EGCG-CGA and EGC-CGA had very similar inhibitory effects on the growth of human colon cancer cells with that of theaflavin 3,3'-digallate. These findings shed light on the interactions between the major bioactive compounds, catechins, and other minor compounds in tea. The confirmation of the presence of this type of reaction in black tea may provide more understanding of the complexity of black tea chemistry.