Abstract Separator is an essential component for lithium-ion batteries, subtly providing transporting micro-channels for lithium ions and electric insulation between electrodes. In this paper, bleached eucalyptus cellulose pulp is implanted with TEMPO-mediated oxidization and high-pressure homogenization to attain cellulose pulps with both micro- and nano-sized fibers, where the blending ratio is regulated by homogenization times. Then the cellulose pulp is formed into separators through vacuum filtration after uniformly dispersed. Macro-properties, micro-structures, physical properties and electrochemical performance of the cellulosic separators are characterized and analyzed. And t commercial Celgard 2500 polypropylene separator is also investigated as comparison. The influence of homogenizing degree on comprehensive properties of the separators is investigated. Besides, the relationship between micro-structure and electrochemical performance is detailedly discussed. Results show that higher homogenization degree contributes to more nano-sized fibers and less micro-fibers, resulting in smaller porosity, poorer electrolyte uptake and larger contact angle. The nano-sized fibers are effective in promoting mechanical strength of separators, but are negative to the impedance performance. This study has unveiled the impact of high-pressure homogenization on the performance of separators, providing meaningful instruction for further development of qualified cellulose separators.

中文翻译：

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揭示均质化程度对 TEMPO 介导的锂离子电池氧化纤维素隔膜电化学性能的影响

摘要 隔膜是锂离子电池的重要组成部分，巧妙地为锂离子提供传输微通道和电极之间的电绝缘。在本文中，漂白的桉树纤维素纸浆被植入TEMPO介导的氧化和高压均质，以获得具有微米和纳米尺寸纤维的纤维素纸浆，其中混合比例通过均质时间进行调节。然后将纤维素纸浆均匀分散后，通过真空过滤形成隔膜。对纤维素隔膜的宏观性能、微观结构、物理性能和电化学性能进行了表征和分析。并且还研究了商用 Celgard 2500 聚丙烯隔板作为比较。研究了均质化程度对隔膜综合性能的影响。此外，详细讨论了微观结构与电化学性能之间的关系。结果表明，均质化程度越高，纳米纤维越多，微纤维越少，孔隙率越小，电解质吸收越差，接触角越大。纳米纤维可有效提高隔膜的机械强度，但对阻抗性能不利。该研究揭示了高压均质对隔膜性能的影响，为进一步开发合格的纤维素隔膜提供了有意义的指导。结果表明，均质化程度越高，纳米纤维越多，微纤维越少，孔隙率越小，电解质吸收越差，接触角越大。纳米纤维可有效提高隔膜的机械强度，但对阻抗性能不利。该研究揭示了高压均质对隔膜性能的影响，为进一步开发合格的纤维素隔膜提供了有意义的指导。结果表明，均质化程度越高，纳米纤维越多，微纤维越少，孔隙率越小，电解质吸收越差，接触角越大。纳米纤维可有效提高隔膜的机械强度，但对阻抗性能不利。该研究揭示了高压均质对隔膜性能的影响，为进一步开发合格的纤维素隔膜提供了有意义的指导。