In Ukrainian

Abstract

Replacing intercalated graphite in traditional lithium-ion batteries with conversion anode material gives an advantage in increasing specific energy at a lower price. A significant drawback of is its very large swelling when saturated with lithium, with the growth of mechanical loads in the bulk of the electrode layer. Direct use of silicon, even nanoscale, is impossible without modifying the interface of the silicon | A stable cycling is shown of electrodes based on the nanocomposite Si@SiOC&C (0D E micro-3D) with a high content (9nano-S@1SiOC&C by mass), active electrically conducting additive of synthetic graphite KS6 and vinylidene fluoride polymer binder in traditional ethylene carbonate electrolyte. The effect is discussed of carbon-enriched oxycarbide (glass-like carbon) – SiOC&C, as a modifier of the silicon | interface, synthesized using polymethylphenylsiloxane, on their electrochemical behavior. Formation of structurally-integrated phase boundary in the synthesis of the composite, the high mechanical strength of the glass-like carbon, the capability of SiOC&C to set up a relatively large amount of lithium in its bulk and a low electrocatalytic activity of this material in relation to organic electrolyte allows to accommodate without cracking the volume changes of silicon, solving the problem of preventing destruction carbon coating of active nanoparticles during long-term cycles of electrodes. Glass-like carbon material can also contribute to the phase transition of the cubic α-Li 15 Si 4 , with the formation of which the volume of the original increases by 280 %, to a denser ortorombic β-Li 15 Si 4 , with a smaller increase in volume (by 210 %). Therefore, the usual vinylidene fluoride polymer binder for graphite anode of lithium-ion batteries can provide effective electrical contact between the particles of the active material and the current collector. These electrodes are effective for use in high-energy lithium-ion superbatteries.