数值模拟是开发与改进锂离子电池的有力工具。对相关电解溶液的传质过程进行建模，需要精确测定相应的电解液参数。本工作尝试测量一种体系的电导率、扩散系数、迁移数和热力学因子，该体系为0.5 M LiPF₆溶解于碳酸乙烯酯与碳酸甲乙酯混合溶剂（EC:EMC，质量比3:7）中，测试温度为20 °C和50 °C。然而，对对称金属Li | 电解液+隔膜 | Li金属电池施加恒电流极化实验后发现，其电位响应在定性上偏离理论预期。受阻的扩散过程表明Li电极上存在额外的、不希望出现的多孔结构，从而妨碍了对电解液参数的可靠评估。为了在频谱上分辨扩散过程，我们进行了极低频阻抗谱测试。阻抗谱实际上表现出多个相互干扰的扩散特征。但在我们的测量中，无法明确识别仅由穿过隔膜的扩散所对应的阻抗。因此，作者怀疑使用Li金属电极的极化实验能否为电解液提供准确的参数。
英文摘要：
Numerical simulations are a powerful tool for the development and improvement of Li-ion batteries. Modeling the mass transport of the involved electrolytic solutions requires precise determination of the corresponding electrolyte parameters. In this work, we attempt to measure the conductivity, the diffusion coefficient, the transference number and the thermodynamic factor for a system of 0.5$\,$M LiPF$_6$ dissolved in a blend of ethylene carbonate and ethyl methyl carbonate (EC:EMC, 3:7 weight) at 20$\,$°C and 50$\,$°C. Applying galvanostatic polarization experiments to symmetrical metal Li | electrolyte + separator | Li metal cells reveals, however, a potential response qualitatively deviating from theoretical expectations. Impeded diffusion processes indicate the presence of additional, undesired porous structures on the Li electrodes, preventing a reliable evaluation of the electrolyte parameters. To spectrally resolve the diffusive processes, we conduct very-low-frequency impedance spectroscopy. The impedance in fact exhibits multiple interfering diffusive features. In our measurements, an explicit identification of the impedance for the sole diffusion through the separator is however not feasible. Therefore, the authors doubt that polarizing experiments using Li metal electrodes yield accurate parameters for electrolytes.
Identifying the Structural Basis for the Increased Stability of the Solid Electrolyte Interphase Formed on Silicon with the Additive Fluoroethylene Carbonate
Computational Study of Li+ Solvation Structures in Fluorinated Ether, Non-Fluorinated Ether, and Organic Carbonate-Based Electrolytes at Low and High Salt Concentrations
从CO2的捕获到其电化学升级的CO2稳定过程需要在捕获、升级和分离步骤中的每一个步骤中进行大量投入。在捕获和释放阶段之后进入CO2电还原阶段的气相CO2进料产生大量的CO2废物，80%至95%的CO2由于碳酸盐形成或电解质渗透而被浪费，这增加了系统的CO2管理方面的成本和能耗。在这里，我们报告了一种电解槽，它直接将碳酸盐电解质从CO2捕集溶液升级为合成气，在整个系统中实现100%的碳利用率。双极膜用于在施加的电势下原位产生质子，其促进在膜：催化剂界面处从碳酸盐溶液释放CO2。使用Ag催化剂，我们以3：1的H2与CO比率产生纯合成气，在气体出口处没有CO2稀释，电流密度为150 mA cm-2，并实现35%的全电池能量效率。直接碳酸盐电池在约100 ℃下连续催化运行145 h，电池性能稳定。180 mA cm-2。这项工作表明，将CO2电解直接与CO2捕获系统相结合可以加速可行的CO2转化技术的发展。
