A Protection Route Based on the Dual-Mode Transfer of Lithium Ions for Lithiophilic Site during the Nucleation Period

Lithiophilic sites with high binding energy to lithium have a positive effect on the induction of Li deposition. However, saturation deposition of Li-ions on lithiophilic sites causes a loss of lithiophilicity. Herein, a protection route of lithiophilic sites during the nucleation period is proposed for the first time. The designed heterointerface provides a directional built-in electric field and a lithiophilic potential well. Li-ions in the space field can nucleate on the semiconductor side by crossing metal-based lithiophilic sites through the electric field-driven mode and the chemical field-driven mode. Based on a high-efficiency dual-mode transfer pathway for Li-ions, which ensures continuous exposure of lithiophilic sites to the electric field and maximizes its positive effect during the nucleation period. A full cell utilizing the LiFePO4 cathode exhibits a stable voltage profile with low polarization for over 200 cycles at 1 C, demonstrating the importance of the continued role of the lithiophilic sites. This work provides a new direction to design lithiophilic sites in Li metal batteries, which can be extended to other alkali metal batteries. Directional built-in electric fields and lithiophilic potential wells drive lithium ions across the metal-based lithophilic sites to nucleate on the semiconductor side, ensuring that the lithiophilic sites are continuously exposed in the spatial field during nucleation. This effectively prevents the inactivation of lithiophilic sites due to the rapid accumulation of lithium ions.image

Automated summary

This study proposes a method to protect lithiophilic sites during the nucleation period by designing a heterointerface that provides a directional built-in electric field and a lithiophilic potential well. Through a high-efficiency dual-mode transfer pathway, lithiophilic sites are continuously exposed to the electric field to maximize their positive effect. The designed full cell demonstrates the importance of the continued role of lithiophilic sites by exhibiting a stable voltage profile at 1 C for over 200 cycles.