Abstract Recently, the scientific interest in developing rechargeable aluminium-ion (Al-ion) batteries has increased, triggered by its theoretical capacity, low cost and low reactivity of aluminium metal. One of the main challenges is the development of cathode materials that reversibly intercalate AlCl4− in its structure. The most promising candidates are carbonaceous materials of very different nature. However, no systematic analysis has been performed so far to investigate the intrinsic parameters that determine their electrochemical performance. Here, different commercial available carbons such as pyrolytic graphite (PG), expanded graphite (EG), synthetic graphitic flakes (SGF) and two different carbon papers (H23C3 and H23I1) are systematically evaluated as cathodes in Al-ion batteries. The influence of their graphitic degree, particle size, porosity and mass loading on the battery performance is elucidated. Electrochemical tests combined with ex situ XRD demonstrated that only highly graphitic materials can intercalate AlCl4− obtaining a good battery performance. Synthetic graphite flakes (SGF) showed the best specific capacity (85 mAh g−1), rate capability and cycle life (>1600 cycles) due to the fast diffusion of the AlCl4− through its structure. Finally, high mass loading cathodes (SGF-HML) showed extraordinary areal capacity (5.6 mAh cm−2), almost doubling the high energy cathodes for Li-ion batteries (3 mAh cm−2).

中文翻译：

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广泛商用的碳质材料作为铝离子电池的阴极

摘要 近年来，由于铝金属的理论容量、低成本和低反应性，开发可充电铝离子（Al-ion）电池的科学兴趣增加了。主要挑战之一是开发在其结构中可逆地嵌入 AlCl4− 的正极材料。最有希望的候选者是性质非常不同的碳质材料。然而，到目前为止，还没有进行系统分析来研究决定其电化学性能的内在参数。在这里，不同的市售碳，如热解石墨 (PG)、膨胀石墨 (EG)、合成石墨薄片 (SGF) 和两种不同的碳纸（H23C3 和 H23I1）被系统地评估为铝离子电池的正极。它们的石墨度、粒径、阐明了孔隙率和质量负载对电池性能的影响。电化学测试与非原位 XRD 相结合表明，只有高度石墨化的材料才能嵌入 AlCl4− 获得良好的电池性能。由于 AlCl4- 通过其结构的快速扩散，合成石墨薄片 (SGF) 显示出最佳的比容量 (85 mAh g-1)、倍率性能和循环寿命（> 1600 次循环）。最后，高质量负载阴极（SGF-HML）显示出非凡的面积容量（5.6 mAh cm-2），几乎是锂离子电池高能阴极（3 mAh cm-2）的两倍。由于 AlCl4- 通过其结构的快速扩散，合成石墨薄片 (SGF) 显示出最佳的比容量 (85 mAh g-1)、倍率性能和循环寿命（> 1600 次循环）。最后，高质量负载阴极（SGF-HML）显示出非凡的面积容量（5.6 mAh cm-2），几乎是锂离子电池高能阴极（3 mAh cm-2）的两倍。由于 AlCl4- 通过其结构的快速扩散，合成石墨薄片 (SGF) 显示出最佳的比容量 (85 mAh g-1)、倍率性能和循环寿命（> 1600 次循环）。最后，高质量负载阴极（SGF-HML）显示出非凡的面积容量（5.6 mAh cm-2），几乎是锂离子电池高能阴极（3 mAh cm-2）的两倍。