headlines, [3][4][5] for which the highly flammable nonaqueous electrolytes used in LIBs are mainly responsible. It is under this context that aqueous LIBs (ALIBs) are revisited as a fundamental solution to safety, despite their low energy densities due to the narrow electrochemical stability window of water. [2,[6][7][8][9][10] Recently, a new class of high-voltage aqueous electrolyte was discovered by dissolving 21 molality (mol) lithium bis(trifluoromethane sulfonyl) imide (LiTFSI) in 1 kg of water. Such a "water-in-salt" electrolyte (WiSE) expands the electrochemical stability window from 1.23 to 3.0 V, which supports a 2.5 V chemistry using LiMn 2 O 4 (LMO) cathode and Mo 6 S 8 anode to stably deliver ≈100 Wh kg −1 for thousand cycles. The significantly improved electrochemical stability therein mainly comes from the depletion of free water molecules and the formation of an anion-derived solid-electrolyte interphase (SEI) on the anode surface. [9] However, because of the intrinsic repulsion of anions and adsorption of the Li + -4(H 2 O) solvates by the negatively polarized anode surface, [4] the formation of such an anion-derived SEI has been impossible below 1.9 V versus Li + /Li. [9] This "cathodic challenge" has essentially excluded many desired energy-dense anodes that operate at low potentials such as Li-metal, graphite, or silicon. Even Li 4 Ti 5 O 12 (LTO) that operates at mild potential (≈1.70 V Li + /Li in WiSE) suffers from irreversibility, because it sits right on the edge of the cathodic limit in WiSE. Efforts aiming to resolve the "cathodic challenge" with additional lithium salts such as lithium trifluoromethane sulfonate (LiOTf) [11] or lithium bis(pentafluoroethane sulfonyl) imide (LiBETI) [10] achieved limited success, because solubility limits of the salts impose restrictions on how high their concentration can go, while the effectiveness of added anions still faces intrinsic resistance from anode surface against their accumulation at inner-Helmholtz layer, not to mention that these additional salts further worsen the already problematic viscosity and ionic conductivity of WiSE. Introducing a nonaqueous solvent, dimethyl carbonate (DMC), [12] into WiSE expands the electro chemical window of the hybrid electrolyte to 4.1 V, because the neutral solvent is less sensitive to anode repulsion and hence participates in interphasial chemistry more easily than anions. The additional protection from an SEI consisting of both anion-and solvent-derived products enables LTO operation Although the "water-in-salt" electrolyte has significantly expanded the electrochemical stability window of aqueous electrolytes from 1.23 to 3 V, its inevitable hydrogen evolution under 1.9 V versus Li + /Li prevents the practical use of many energy-dense anodes. Meanwhile, its liquidus temperature at 17 °C restricts its application below ambient temperatures. An advanced hybrid electrolyte is proposed in this work by introducing acetonitrile (AN) as co-solvent, which minimizes the presence of interfacial water at the nega...
Carbonate-based electrolytes have been extensively employed in commercial Li-ion batteries, but they faces numerous interphasial stability challenges while supporting the high-voltage cathode chemistries and lithium metal anode, which result in...
Qiliqiangxin capsule (QLC), a natural herb recipe with therapeutic effect from China, has been widely used in clinical practice for attenuating cardiac remodeling induced by myocardial infarction (MI). However, the pharmacological mechanism of QLC on cardiac remodeling after MI is not entirely clear. The present study aims to investigate the effectiveness and mechanisms of QLC on cardiac remodeling induced by MI in rats. The animal model was established by permanently ligating the left anterior descending coronary artery in rats. Subsequently, rats with successful ligation were randomly divided into model group, captopril group, and QLC group. And the control group was operated upon in parallel except ligation, namely, the sham group. All rats were treated through the intragastric administration once a day for 4 weeks. Cardiac hemodynamics was measured after treatment. Then, the left ventricular mass index (LVMI) was examined. The pathological changes were observed by HE staining. The collagen volume fraction (CVF) was detected by Masson trichrome staining. The apoptosis index was obtained by TUNEL fluorescent staining. The miR-133a and mRNA of TGF-β1, CTGF, Caspase9, and Caspase3 were examined by real-time PCR. The protein expressions of TGF-β1, CTGF, Caspase9, Caspase3, and cleaved-Caspase3 were tested by Western blot. Compared with the model group, QLC partially improved cardiac hemodynamics and decreased LVMI. miR-133a was significantly increased in QLC group. In addition, QLC declined CVF by downregulating TGF-β1 rather than CTGF. Meanwhile, QLC decreased the apoptosis index by attenuating Caspase9, Caspase3, and cleaved-Caspase3. This study suggested that QLC could improve cardiac function and partially attenuate cardiac remodeling by attenuating fibrosis and decreasing apoptosis, which might be partially related to miR-133a, TGF-β1, Caspase9, and Caspase3.
The operating voltage of lithium–nickel–manganese oxide (LiNi0.5Mn1.5O4, LNMO) cathodes far exceeds the oxidation stability of the commercial electrolytes. The electrolytes undergo oxidation and decomposition during the charge/discharge process, resulting in the capacity fading of a high-voltage LNMO. Therefore, enhancing the interphasial stability of the high-voltage LNMO cathode is critical to promoting its commercial application. Applying a film-forming additive is one of the valid methods to solve the interphasial instability. However, most of the proposed additives are expensive, which increases the cost of the battery. In this work, a new cost-efficient film-forming electrolyte additive, 4-trifluoromethylphenylboronic acid (4TP), is adopted to enhance the long-term cycle stability of LNMO/Li cell at 4.9 V. With only 2 wt % 4TP, the capacity retention of LNMO/Li cell reaches up to 89% from 26% after 480 cycles. Moreover, 4TP is effective in increasing the rate performance of graphite anode. These results show that the 4TP additive can be applied in high-voltage LIBs, which significantly increases the manufacturing cost while improving the battery performance.
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