Diffusion Enhancement to Stabilize Solid Electrolyte Interphase. Issue 40 (21st September 2021)

• Record Type: Journal Article
• Authors: Chen, Yunyi; Huang, Haoyang; Liu, Lingli; Chen, Yongxiu; Han, Yongsheng
• Is Part Of: Advanced energy materials. Volume 11:Issue 40(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-09-21
• Subjects: diffusion enhancement -- lithium‐metal anodes -- lithium stripping -- magnetic field -- solid electrolyte interphase; Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.202101774
• Languages: English
• ISSNs: 1614-6832

Abstract

Abstract: The damage of the solid electrolyte interphase (SEI) layer during the stripping process in lithium secondary batteries causes the reduction of energy density. The stabilization of the solid electrolyte interphase is as important as the inhibition of lithium dendrites for lithium‐based batteries. But the former is largely underestimated, which leads to the unclear damage mechanism and the lack of effective solutions to suppress the damage. Here, in this paper a diffusion‐limited damage mechanism of the SEI layer is proposed. The inhomogeneity of the SEI layer results in region‐dependent diffusion kinetics of lithium ions (Li + ) passing through the layer. The slip lines and kinks having a thicker SEI layer, show slower Li + conduction than the smooth surface. The uneven stripping process leads to the formation of cracks at the boundary between the slip lines and the smooth surface, which further causes collapse and serious damage of SEI. Upon this assumption, it is proposed to enhance the diffusion of Li + at the local areas of SEI layer by applying parallel magnetic fields on the outside of electrodes. Both the electrochemical characterizations and long‐term stability examination confirm the effectiveness of the magnetic field in enhancing the diffusion of Li + and suppressing the damage of SEI. Abstract : A diffusion‐limited damage mechanism of the solid electrolyte interphase (SEI) layer in secondary batteries is proposed and confirmed by a diffusion enhancement strategy. By applying an external parallel magnetic field in a discharging process, the rupture of the SEI layer is eliminated and the life and performance of batteries are largely improved.