To date, enhancing the specific energy of LiCoO₂/graphite batteries by increasing the cut-off charging voltage through the strategy of adding multifunctional additives in the electrolyte it is still an effective method and research hotspot. In this paper, 4-hydroxy-2-butanesulfonic acid gamma-sultone (HBAG) is demonstrated as an effective bifunctional electrolyte additive to improve the electrochemical performances of 4.4 V LiCoO₂/graphite batteries. With the addition of 1.0% HBAG in the electrolyte, a capacity retention of 94.88% after 160 cycles can be obtained when the batteries are cycled in the voltage range of 3.0–4.4 V at 25 °C, which is much higher than the batteries with the base electrolyte (54.77%). It is indicated that the HBAG additive in the electrolyte is preferentially decomposed on two electrodes, which facilitates the formation of thin and uniform films on the cathode and anode. In particular, the interface films possess excellent Li⁺ intercalation/deintercalation properties and can prevent further decomposition of the electrolyte, resulting in battery performance improvement. These results indicate that the HBAG-containing electrolyte has promising prospects for application in high-voltage LiCoO₂/graphite batteries with good performance.

中文翻译：

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4-羟基-2-丁烷磺酸γ-磺内酯作为双功能电解质添加剂，用于具有增强性能的LiCoO ₂ /石墨电池

迄今为止，通过在电解液中添加多功能添加剂的策略，通过提高充电截止电压来提高LiCoO ₂ /石墨电池的比能量仍然是一种有效的方法和研究热点。在本文中，4-羟基-2-丁磺酸γ-磺内酯（HBAG）被证明是一种有效的双功能电解质添加剂，可提高 4.4 V LiCoO ₂的电化学性能/石墨电池。在电解液中加入 1.0% HBAG 后，电池在 3.0-4.4 V 电压范围内、25°C 条件下循环 160 次后的容量保持率可达到 94.88%，远高于含 HBAG 的电池。基础电解质 (54.77%)。表明电解液中的 HBAG 添加剂优先在两个电极上分解，这有利于在阴极和阳极上形成薄而均匀的薄膜。特别是界面膜具有优异的Li ⁺嵌入/脱嵌性能，可以防止电解液的进一步分解，从而提高电池性能。这些结果表明，含 HBAG 的电解质在高压 LiCoO _{2 中}具有广阔的应用前景。/石墨电池具有良好的性能。