We report an ultrafast in-situ laser reduction process of graphene oxides (GO) in LiFePO₄ electrodes, where the selective laser reduction of GO sheets is conducted after coating LiFePO₄ on current collector. This novel process technique avoids the solvophobicity and agglomeration problems of graphene in 1-methyl-2-pyrrolidinone (NMP) or other solvents for the electrode material slurry preparation because of GO's solvophilicity in various solvents. Under the optimized laser reduction condition, a hierarchical structure of graphene conductive network is formed without wrapping the LiFePO₄ surface, which can greatly improve the rate capability and cycle performance. The battery capacity remains 84.5% after 1000 cycles and 72.9% when the charge/discharge current density increases from 0.5C to 20C. The method developed in this work is also applicable for other material systems to selectively reduce GO for performance enhancement.

我们报告了LiFePO ₄电极中石墨烯（GO）的超快原位激光还原过程，其中，在集电器上涂覆LiFePO ₄后，进行GO片材的选择性激光还原。这种新的工艺技术避免了石墨烯在1-甲基-2-吡咯烷酮（NMP）或用于电极材料浆料制备的其他溶剂中的疏溶剂性和团聚问题，因为GO在各种溶剂中具有亲溶剂性。在优化的激光还原条件下，无需包裹LiFePO ₄即可形成石墨烯导电网络的分层结构表面，可以大大提高速率能力和循环性能。电池容量在1000次循环后仍保持84.5％，在充放电电流密度从0.5C增加到20C时保持72.9％。在这项工作中开发的方法还适用于其他材料系统，以选择性地降低GO的性能。