The Li-CO₂ battery is a newly-emerging energy storage and conversion system, making CO₂ renewable utilization and capture in a green way. However, the unsatisfactory electrochemical performances such as high polarization, short cyclic life and poor rate capability caused by the sluggish decomposition the product Li₂CO₃ and the lacking of mechanical flexibility due to the rigid cathode, greatly hinder its real application, especially for the compliant and wearable devices. Herein, the vertically aligned N-doped carbon nanotube (VA-NCNT) arrays on Ti wire are prepared as freestanding, binder-free cathodes for flexible quasi-solid-state Li-CO₂ battery. The VA-NCNT arrays have thousands of vertical CNT with high N-doping percentage, rich defects and void space, which facilitate the CO₂ diffusion and electrolyte permeation, provide exposed active sites and more space for the formation and accommodation of Li₂CO₃ and help the oxidation of Li₂CO₃ and amorphous carbon in charge process. As a result, the fabricated battery shows ultralong cycle life, small potential gap, outstanding rate capability and high flexibility. Our work provides an alternative option towards CO₂ conversion and utilization as high performance energy sources.

Li-CO ₂电池是一种新兴的能量存储和转换系统，使CO ₂可再生利用并以绿色方式捕获。然而，由于Li ₂ CO ₃产物的分解缓慢而导致电化学性能不理想，如极化率高，循环寿命短和倍率性能差，以及由于刚性阴极而导致的机械柔韧性不足，极大地阻碍了其实际应用，特别是对兼容且可穿戴的设备。在此，将Ti线上的垂直排列的N掺杂碳纳米管（VA-NCNT）阵列制备为用于柔性准固态Li-CO _2的独立无粘结剂阴极电池。VA-NCNT阵列具有成千上万的垂直CNT，具有较高的N掺杂百分比，丰富的缺陷和空隙空间，这有助于CO ₂扩散和电解质渗透，提供了暴露的活性位点，并为Li ₂ CO ₃的形成和容纳提供了更多空间。并在充电过程中帮助Li ₂ CO ₃和非晶碳氧化。结果，制成的电池显示出超长的循环寿命，小的电势差，出色的倍率能力和高柔韧性。我们的工作提供了向CO的替代选项₂转换和利用作为高性能能源。