Electrochemical properties and working mechanisms of benzyl isocyanate compounds as polymerizable electrolyte additives for overcharge protection of lithium ion batteries have been studied by cyclic voltammetry, charge–discharge cycling, overcharge tests, accelerating rate calorimetry (ARC) and in situ Fourier transform infrared spectroscopy (FTIRS). The overcharge and FTIRS data clearly reveal that 4-bromobenzyl isocyanate (Br-BIC) can electrochemically polymerize at 5.5 V (versus Li/Li⁺) to form an overcharge-inhibiting (probably insulating) film on the cathode surface. In addition, is found the Br-BIC does slightly improve the charge/discharge performance of a lithium ion battery. Furthermore, Br-BIC and benzyl isocyanate show beneficial solid electrolyte interphase (SEI) formation behaviour on graphite in propylene carbonate based electrolyte solutions.

中文翻译：

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4-溴苄基异氰酸酯与异氰酸苄基酯—锂离子电池用新型成膜电解质添加剂和过充保护添加剂

通过循环伏安法，充放电循环，过充电试验，加速量热法（ARC）和原位傅立叶变换红外光谱（FTIRS），研究了异氰酸苄酯化合物作为可聚合电解质添加剂的可充电电解质添加剂的电化学性能和工作机理。 ）。过充电和FTIRS数据清楚地表明，异氰酸4-溴苄酯（Br-BIC）可以在5.5 V下发生电化学聚合（相对于Li / Li ⁺）在阴极表面上形成过充电抑制（可能是绝缘的）膜。另外，发现Br-BIC确实稍微改善了锂离子电池的充电/放电性能。此外，Br-BIC和异氰酸苄酯在碳酸亚丙酯基电解质溶液中在石墨上显示出有益的固体电解质相间（SEI）形成行为。