Park Joong Sun, Mane Anil U, Elam Jeffrey W, Croy Jason R
Chemical Sciences and Engineering Division and Energy Systems Division, Argonne National Laboratory, Argonne, Illinois 60439, United States.
ACS Omega. 2017 Jul 19;2(7):3724-3729. doi: 10.1021/acsomega.7b00605. eCollection 2017 Jul 31.
Atomic layer deposition (ALD) of the well-known AlO on a LiCoO system is compared with that of a newly developed AlW F material. ALD coatings (∼1 nm thick) of both materials are shown to be effective in improving cycle life through mitigation of surface-induced capacity losses. However, the behaviors of AlO and AlW F are shown to be significantly different when coated directly on cathode particles versus deposition on a composite electrode composed of active materials, carbons, and binders. Electrochemical impedance spectroscopy, galvanostatic intermittent titration techniques, and four-point measurements suggest that electron transport is more limited in LiCoO particles coated with AlO compared with that in particles coated with AlW F . The results show that proper design/choice of coating materials (e.g., AlW F ) can improve capacity retention without sacrificing electron transport and suggest new avenues for engineering electrode-electrolyte interfaces to enable high-voltage operation of lithium-ion batteries.
将在LiCoO体系上进行的著名的AlO的原子层沉积（ALD）与新开发的AlW F材料的原子层沉积进行了比较。两种材料的ALD涂层（约1nm厚）均显示出通过减轻表面诱导的容量损失来有效提高循环寿命。然而，当直接涂覆在阴极颗粒上与沉积在由活性材料、碳和粘合剂组成的复合电极上时，AlO和AlW F的行为显示出显著差异。电化学阻抗谱、恒电流间歇滴定技术和四点测量表明，与涂覆有AlW F的颗粒相比，涂覆有AlO的LiCoO颗粒中的电子传输受到更多限制。结果表明，涂层材料（如AlW F）的合理设计/选择可以在不牺牲电子传输的情况下提高容量保持率，并为设计电极-电解质界面以实现锂离子电池的高压运行提出了新途径。
