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Conventional battery electrodes have high tortuosity, which severely impedes ion transport. This limitation restricts electrode thickness, decreases power density, and shortens battery lifetime. Fabricating through holes can reduce tortuosity, but existing methods are generally complex and lead to poor space utilization. Here, an array of high-density through-holes are fabricated by temporally shaped ultraviolet femtosecond laser. Using this technique, we achieve a 47:1 aspect ratio (6 μm in diameter), ensuring minimal material loss (< 1%) for 280 μm-thick electrodes. The through-hole array reduces the tortuosity of thick electrodes by 22.9%-33.4%, thereby boosting the gravimetric energy density of batteries by 9.39%, 12.27%, and 17.39% at 1 C, 1.5 C, and 2 C, respectively. It can also increase the power density by 100% - 400%, and double the cycling lifetime. This work demonstrates an effective approach for fabricating low-tortuosity electrodes, which can significantly enhance the comprehensive performance of batteries

传统电池电极普遍存在曲折度较高的问题，会严重阻碍离子传输。该缺陷会限制电极厚度提升、降低电池功率密度并缩短循环寿命。制备通孔结构可有效降低电极曲折度，但现有工艺普遍存在流程复杂、空间利用率低下的弊端。本研究采用时域整形紫外飞秒激光（ultraviolet femtosecond laser）制备出高密度通孔阵列，实现了孔径6μm、长径比47:1的通孔结构，在加工280μm厚的电极时可将材料损耗控制在<1%的水平。该通孔阵列可将厚电极的曲折度降低22.9%~33.4%，进而使电池在1C、1.5C及2C倍率下的重量能量密度分别提升9.39%、12.27%与17.39%；同时可将功率密度提升100%~400%，并使循环寿命翻倍。本研究提出了一种制备低曲折度电极的高效工艺，可显著提升电池的综合性能。