New Lithium Solid-State Batteries with Asymmetrical Polymer Nanocomposite Electrolyte and LiFePO4 Cathode, “Liquid Phase Therapy” Effect

• Published in: Russian journal of general chemistry Vol. 94; no. 6; pp. 1569 - 1573
• Main Authors: Slesarenko, A. A., Baymuratova, G. R., Slesarenko, N. A., Tulibaeva, G. Z., Yudina, A. V., Yarmolenko, O. V.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 2024; Springer Nature B.V
• Subjects: Anodic dissolution; Asymmetry; Butyrolactone; Cathodes; Cathodic dissolution; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Composition effects; Crystal structure; Diffusion coefficient; Dissolution; Electrolytes; Liquid phases; Lithium; Lithium isotopes; Nanocomposites; NMR; Nuclear magnetic resonance; Olivine; Polyethylene glycol; Polymer gels; Polymers; Selected articles originally published in Russian in Rossiiskii Khimicheskii Zhurnal (Russian Chemistry Journal); Self diffusion; Silicon dioxide; Solid state; Solvation; Therapy; “liquid-phase therapy,” solid-state lithium battery; LiFePO; cathode; nanocomposite polymer electrolyte
• ISSN: 1070-3632; 1608-3350
• DOI: 10.1134/S1070363224060392

New lithium solid–state batteries with an asymmetric polymer nanocomposite electrolyte based on polyethylene glycol diacrylate and SiO 2 have been developed, the use of which made it possible to obtain the theoretical capacity of the LiFePO 4 cathode. To achieve non-dendritic and non-corrosive highly reversible deposition/dissolution of lithium, the nanocomposite polymer solid state electrolyte can be positioned on the lithium anode side. In turn, the so-called “liquid-phase therapy” can facilitate the simple intercalation of lithium into the olivine crystal structure to ensure high charge/discharge cycleability of the battery by applying microscopic amounts of liquid electrolyte to the surface of the porous LiFePO 4 cathode. Electrolytes based on LiBF 4 and LiN(CF 3 SO 2 ) 2 salts in gamma-butyrolactone, dioxolane, and dimethoxyethane were investigated by pulsed field gradient NMR on 7 Li nuclei and by electrochemical impedance. It has been shown that the “liquid-phase therapy” of the polymer electrolyte/porous cathode interface effectively increases the electrode reaction only in the case of a liquid electrolyte composition of 1 M LiN(CF 3 SO 2 ) 2 in a mixture of dioxolane and dimethoxyethane (1 : 2 vol). The nanocomposite polymer gel electrolyte, which is a 1 M solution of LiBF 4 in gamma-butyrolactone, on the other hand, turns the border non-conductive. The calculated binding energies of the solvate complexes of the lithium cation with the surface of the SiO 2 nanoparticles and the measured lithium self-diffusion coefficients suggest that solvation at the nanocomposite interface in 1 M LiN(CF 3 SO 2 ) 2 in dioxolane/dimethoxyethane is facilitated, whereas solvation at the interface in 1 M LiBF 4 in gamma-butyrolactone is challenging.