The lithium-ion batteries are recognized as the most promising energy storage system, but it still does not meet the power requirements of electric vehicle batteries owing to low volumetric energy density with the traditional graphite electrode system. In this study, we report the development of a novel electrode system fabricated by implantation of a solid electrolyte interphase (SEI) layer on the graphite surface. The SEI-implanted graphite electrode is made using a lithium bis(trifluoromethanesulfonyl)imide (LiTFSI)-based electrolyte and cycled with a lithium tetrafluoroborate LiBF₄-based electrolyte. This new electrode system shows significantly enhanced electrochemical properties owing to the rapid and efficient diffusion of Li ions through the SEI layer between the electrolyte and electrode. This graphite electrode with its pre-formed SEI layer achieves a reversible capacity of 357 mAh g⁻¹ at 0.5 C after 50 cycles, which is significantly higher than that of commercial lithium-ion battery systems constructed with LiPF₆ (312 mAh g⁻¹). The resulting unique electrode system could present a new avenue in SEI research for high-performance lithium-ion batteries.

锂离子电池被认为是最有前途的能量存储系统，但是由于传统石墨电极系统的体积能量密度低，它仍不能满足电动汽车电池的功率要求。在这项研究中，我们报告了通过在石墨表面上植入固体电解质中间相（SEI）层制造的新型电极系统的开发。SEI植入的石墨电极是使用基于双（三氟甲磺酰基）酰亚胺（LiTFSI）的锂制成的，并用四氟硼酸锂LiBF ₄循环电解质。由于锂离子通过电解质和电极之间的SEI层快速有效扩散，这种新的电极系统显示出显着增强的电化学性能。该石墨电极具有预先形成的SEI层，经过50次循环后，在0.5 C下可实现357 mAh g ^-1的可逆容量，这明显高于采用LiPF ₆（312 mAh g ^-1）。由此产生的独特电极系统可以为高性能锂离子电池的SEI研究提供一条新途径。