Fabrication of Borate-Based Porous Polymer Electrolytes Containing Cyclic Carbonate for High-Performance Lithium Metal Batteries

Abstract

A series of borate-based porous polymer electrolytes (B-PPEs) is prepared by incorporating the copolymers containing cyclic boroxine and cyclic carbonate groups into poly­(vinylidene fluoride) (PVDF) through the phase inversion method. The dense and well-interconnected pores are obtained in the polymer matrix when the content of the copolymer reached 40 wt %. The ethylene–oxygen chain segments in the copolymer can facilitate the mobility of polymer chains and form the uniform distribution of pores in the B-PPEs. The B-PPEs show an enhanced ionic conductivity of 1.32 × 10–3 S cm–1 at 30 °C, which is due to the uniform well-interconnected pores in the polymer host. The cyclic carbonate units interact with the liquid electrolyte, which could improve the electrolyte uptake capacity of the polymer matrix. Benefited from the Lewis acid–base interactions between boron moieties and the anions of the lithium salt, the lithium-ion transference number of B-PPEs is also significantly improved. Compared to the pure PVDF-based electrolyte, the Li/B-PPEs/Li cell displays a very stable polarization voltage and the long-time cycling for 1000 h at a current density of 0.2 mA cm–2. Moreover, the Li/B-PPEs/LiFePO4 cells deliver a higher capacity of 143.0 mAh g–1 at 0.2 C and 86% capacity retention after 150 cycles. The B-PPEs could be a promising candidate for enhancing the safety and electrochemical properties of lithium metal batteries.

Solid polymer electrolytes: Ion conduction mechanisms and enhancement strategies

“…Another method for preparing porous polymer matrices such as PVDF-HFP, PAN, PMMA, and PEO is phase inversion, and the generated pores were owing to the different dissolution and evaporation rates of the mixture solvents [224]. Zhou et al [225] synthesized a poly(B-Vd) which contains cyclic boroxine and cyclic carbonate groups by using polyethylene glycol methyl methacrylate (B-PEGMA) (containing boronic acid monomers) and 4-vinyl-1,3-dioxan-2-one (Vd), and then combined the poly(B-Vd) copolymer with the PVDF polymer matrix to prepare borate-based porous polymer electrolytes (B-PPEs) by the phase inversion method (Fig. 28(a)).…”

Boron‐Based High‐Performance Lithium Batteries: Recent Progress, Challenges, and Perspectives

“…This combines the advantages of high ionic conductivity of LEs with the safety of SPEs. Zhou et al [123] prepared a series of boroncontaining porous polymer electrolytes (B-PPEs) by incorporating copolymers containing cyclic boroxane and cyclic carbonate into poly(vinylidene fluoride) (PVDF) by phase inversion (as shown in Figure 8c). The boron-containing GPEs (B-PPE40) exhibited good electrochemical performance when the copolymer content reached 40 wt%.…”

High performance of the sodium‐ion conducting flexible polymer blend composite electrolytes for electrochemical double‐layer supercapacitor applications

“…Traditional energy sources such as coal and fossil fuels are Non‐renewable and limited. Biogas is represented in modern times 1,2 . It is practical and has the potential to meet future needs for energy storage equipment.…”

“…Biogas is represented in modern times. 1,2 It is practical and has the potential to meet future needs for energy storage equipment. The sodium element, which is the sixth richest element in the Earth's crust, is a better choice in the R&D activity and industry applications and has the advantages such as longer shelf life, lower reduction potential (2.7 V), and very low cost (affordable on the side) and seven times cheaper than the important element lithium.…”