Center for Nanochemistry, Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China.
Electron Microscopy Laboratory and International Centre for Quantum Materials, School of Physics, Peking University, Beijing, 100871, P. R. China.
Adv Mater. 2017 Dec;29(47). doi: 10.1002/adma.201703882. Epub 2017 Oct 27.
Aluminum (Al) foil, as the most accepted cathode current collector for lithium-ion batteries (LIBs), is susceptible to local anodic corrosions during long-term operations. Such corrosions could lead to the deterioration or even premature failure of the batteries and are generally believed to be a bottleneck for next-generation 5 V LIBs. Here, it is demonstrated that Al foil armored by conformal graphene coating exhibits significantly reinforced anodic corrosion resistance in both LiPF and lithium bis(trifluoromethanesulphonyl) imide (LiTFSI) based electrolytes. Moreover, LiMn O cells using graphene-armored Al foil as current collectors (LMO/GA) demonstrate enhanced electrochemical performance in comparison with those using pristine Al foil (LMO/PA). The long-term discharge capacity retention of LMO/GA cell after ≈950 h straight operations at low rate (0.5 C) reaches up to 91%, remarkably superior to LMO/PA cell (75%). The self-discharge propensity of LMO/GA is clearly relieved and the rate/power performance is also improved with graphene mediations. This work not only contributes to the long-term stable operations of LIBs but also might catalyze the deployment of 5 V LIBs in the future.
铝（Al）箔作为锂离子电池（LIBs）最常用的阴极集流器，在长期运行过程中容易发生局部阳极腐蚀。这种腐蚀会导致电池恶化甚至提前失效，通常被认为是下一代 5V LIBs 的瓶颈。本文证明，通过共形石墨烯涂层包覆的铝箔在 LiPF 和双（三氟甲烷磺酰基）亚胺锂（LiTFSI）基电解质中表现出显著增强的阳极耐腐蚀性。此外，使用石墨烯包覆铝箔作为集流器的 LiMn O 电池（LMO/GA）与使用原始铝箔（LMO/PA）的电池相比，表现出增强的电化学性能。在低速率（0.5C）下进行 ≈950 小时的直排运行后，LMO/GA 电池的长期放电容量保持率高达 91%，明显优于 LMO/PA 电池（75%）。LMO/GA 的自放电趋势明显缓解，并且石墨烯的介入也改善了其倍率和功率性能。这项工作不仅有助于 LIBs 的长期稳定运行，而且可能会促进 5V LIBs 的未来应用。
