南京邮电《Carbon》:卷对卷制备超薄类石墨非晶碳膜修饰铝箔集流体,用于高压LiNi₀.₅Mn₁.₅O₄锂离子电池

图1。制作工艺、数码照片、GAC@Al箔的形态学和结构特征分析。

图2. Anti-corrosion performance characterizations of bare Al, CC@Al and GAC@Al-20 nm, GAC@Al-30 nm and GAC@Al-50 nm foils. (a) LSV curves in LiPF₆ electrolyte at a sweep rate of 1.0 mV s⁻¹. (b) F 1s XPS fine spectra after LSV test. (c) CA curves at 4.5 V over 1000 s. High-resolution SEM images and the corresponding EDS mapping of (d) bare Al, (e) CC@Al and (f) GAC@Al-20 nm, (g) GAC@Al-30 nm and (h) GAC@Al-50 nm foils after LSV test. (i) Quantitative statistics of F content from EDS mapping. (j) Schematic diagram of the corrosion process of bare Al, CC@Al and GAC@Al foils in electrolytes.

图3. Electrochemical performances of LNMO/Al, LNMO/CC@Al, LNMO/GAC@Al-20 nm, LNMO/GAC@Al-30 nm and LNMO/GAC@Al-50 nm cells. (a) Rate performance, (b) charge/discharge curves at 5C and (c) Nyquist plots of LNMO/Al, LNMO/CC@Al and LNMO/GAC@Al cells, respectively. Long-term cycling performance at (d) 1C and (e) 5C, respectively. (f) Performance comparison between GAC@Al and other representative protective-coated Al foil current collectors. The numbers 1, 2 and 3 for easy scalability and environmental friendliness indicate low, medium and high levels, respectively.

图4. Characterization of the graphite/Cu//LNMO/GAC@Al pouch full cell. (a) Digital photograph of a timer powered by the pouch full cell. (b) Rate performance, (c) long-term cycling performance and (d) charge-discharge curves at 2C of the pouch full cell.

综上所述，本研究提出了一种卷对卷磁控溅射策略，在铝箔表面连续沉积超薄类石墨非晶碳（g-aC）保护层，显著提升了铝箔集流体在高压电解液中的耐腐蚀稳定性。g-aC修饰层兼具高导电性与化学惰性，有效抑制了高压下铝的溶解与含氟腐蚀产物的生成，同时保持极低的界面接触电阻。将g-aC@Al集流体应用于LiNi₀.₅Mn₁.₅O₄正极，电池展现出更高的可逆容量、更优的倍率性能和显著改善的循环稳定性。该工作为高电压锂离子电池集流体的界面工程提供了可规模化解决方案，具有重要产业化前景。