Uniform Lithium Plating for Dendrite-Free Lithium Metal Batteries: Role of Dipolar Channels in Poly(vinylidene fluoride) and PbZrxTi1- xO3 Interface

Ben-Hao Kang; Shuang-Feng Li; Jinlong Yang; Zhong-Ming Li; Yan-Fei Huang

doi:10.1021/acsnano.3c04684

Uniform Lithium Plating for Dendrite-Free Lithium Metal Batteries: Role of Dipolar Channels in Poly(vinylidene fluoride) and PbZr_xTi_{1- x}O₃ Interface

ACS Nano. 2023 Jul 25;17(14):14114-14122. doi: 10.1021/acsnano.3c04684. Epub 2023 Jul 5.

Authors

Ben-Hao Kang¹, Shuang-Feng Li¹, Jinlong Yang¹, Zhong-Ming Li², Yan-Fei Huang¹

Affiliations

¹ College of Materials Science and Engineering, Shenzhen University, Shenzhen 518055, People's Republic of China.
² College of Polymer Science and Engineering and State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, People's Republic of China.

PMID: 37405783
DOI: 10.1021/acsnano.3c04684

Abstract

Conventional polymer/ceramic composite solid-state electrolytes (CPEs) have limitations in inhibiting lithium dendrite growth and fail to meet the contradictory requirements of anodes and cathodes. Herein, an asymmetrical poly(vinylidene fluoride) (PVDF)-PbZr_xTi_1-xO₃ (PZT) CPE was prepared. The CPE incorporates high dielectric PZT nanoparticles, which enrich a dense thin layer on the anode side, making their dipole ends strongly electronegative. This attracts lithium ions (Li⁺) at the PVDF-PZT interface to transport through dipolar channels and promotes the dissociation of lithium salts into free Li⁺. Consequently, the CPE enables homogeneous lithium plating and suppresses dendrite growth. Meanwhile, the PVDF-enriched region at the cathode side ensures intermediate contact with positive active materials. Therefore, Li/PVDF-PZT CPE/Li symmetrical cells exhibit a stable cycling performance exceeding 1900 h at 0.1 mA cm^-2 at 25 °C, outperforming Li/PVDF solid-state electrolyte/Li cells that fail after 120 h. The LiNi_0.8Co_0.1Mo_0.1O₂/PVDF-PZT CPE/Li cells show low interfacial impedances and maintain stable cycling performance for 500 cycles with a capacity retention of 86.2% at 0.5 C and 25 °C. This study introduces a strategy utilizing dielectric ceramics to construct dipolar channels, providing a uniform Li⁺ transport mechanism and inhibiting dendrite growth.

Keywords: PVDF composite solid-state electrolytes; PZT; dielectric constant; dipolar channels; lithium dendrites.