Vigilancia Tecnológica

Solid?state lithium batteries are promising candidates for the next generation high security and high performance batteries. Here, the lignin derived ultra?thin all?solid composite polymer electrolytes (CPEs) with a thickness of only 13.2 ?m, which possessed three dimensional nanofiber ionic bridge networks composed of single?ion lignin based lithium (L?Li) and poly(vinylidene fluoride?co?hexafluoropropylene) (PVDF?HFP) as the framework, and poly(ethylene oxide)/lithium bis(trifluoromethanesulfonyl)imide (PEO/LiTFSI) as the filler, was obtained through electrospinning/spraying and hot?pressing process. The obtained CPE presented high ionic conductivity of 1.3×10?4 S cm?1, excellent oxidative stability of 4.7 V, and satisfactory tensile strength of up to 9.30 MPa. The Li||Li symmetric cell assembled with the CPE can stably cycle more than 6500 h under 0.5 mA cm?2 with little Li dendrites growth. Moreover, the assembled Li||CPE||LiFePO4 cells can stably cycle over 700 cycles at 0.2 C with a super high initial discharge capacity of 158.5 mAh g?1 at room temperature, and a favorable capacity of 123 mAh g?1 at ?20 °C for 250 cycles, and Li||CPE|| NCM can also stably cycle more than 70 cycles with a favorable discharge capacity of 132.4 mAh g?1 at 0.2 C and 30 °C. The excellent electrochemical performance was mainly attributed to the reason that the nanofiber ionic bridge network can afford uniformly dispersed single?ion L?Li through electrospinning, which synergized with the LiTFSI well dispersed in PEO to form abundant and efficient three dimensional Li+ transfer channels. Furthermore, the ultra?thin CPE can be compactly attached to the lithium anode, and provided a shorter ion transmission distance between the electrodes, inducing uniform deposition of Li+ at the interface, and inhibiting the lithium dendrites. This work provided a promising strategy to achieve ultra?thin biobased electrolytes with high tensile strength and electrochemical performance for solid?state LIBs.This article is protected by copyright. All rights reserved