Thermodynamic analysis and effect of crystallinity for silicon monoxide negative electrode for lithium ion batteries

Abstract

The electrochemical behavior of SiO negative electrodes for lithium ion batteries is thermodynamically and experimentally investigated. The analysis of the reaction pathway and the calculation of the reaction potentials during the Li insertion/extraction reactions are carried out by the construction of the ternary phase diagram for the Li-Si-O system. In the initial reaction of Li insertion, metallic Si and lithium silicates are formed above 0.37 V vs. Li/Li + as a conversion reaction of the SiO negative electrode. Further Li insertion produces Li-Si alloys as reversible reaction phases. The decomposition of the Li 4 SiO 4 phase begins before the formation of the Li-Si alloy is completed. The measured electrode behavior of the SiO negative electrode basically agrees with the thermodynamic calculations, especially at a low reaction rate; deviations can be ascribed to kinetic factors and electrode resistance. The values of over 1898 mA h g −1 and 71.0% were obtained for the discharge capacity and the coulombic efficiency, respectively. Furthermore, the overvoltage for an amorphous SiO electrode was smaller than that for a disproportionated SiO electrode into Si and SiO 2 phases. Highlights-Thermodynamic analysis of SiO electrodes-Highest discharge capacity and relatively high coulombic efficiency for SiO anode-Superior characters of amourphous SiO than disproportionated SiO

Energetics of silica lithiation and its applications to lithium ion batteries

“…As mentioned above, several investigations using SiO 2 as negative electrode for LIB suggest the formation of silicon by electrochemical reduction of silica and the formation of Li 2 O and different lithium silicates as co-products [9,11,[13][14][15][26][27][28].…”

Dopamine-grafted heparin as an additive to the commercialized carboxymethyl cellulose/styrene-butadiene rubber binder for practical use of SiOx/graphite composite anode

“…However, silicon has inherent problems due to volume expansion and shrinkage of about 400% during the charge-discharge process of Si + 4.4Li ⇆ Li 4.4 Si 5 , 6 . When such changes in volume are repeated, mechanical stresses build up that damage the anode, induce its components (e.g., conducting agents and binders) to separate from one another, and cause loss of electrical pathways by isolating Si particles having insulation properties, leading to rapid deterioration of the battery system 9 – 12 . Thus, many researchers have examined modified forms of silicon, for example, nano-sized particles, in order to reduce the stress caused by the volume expansion of Si 13 , 14 .…”

Natural Cellulose Derived Nanocomposites as Anodic Materials for Lithium‐Ion Batteries

“…Although silica-based anodic materials are not as electrochemically active as the silicon-based ones, they have also attracted certain attentions because of the still higher theoretical specific capacity (1965 mAh g À 1 ) as compared with the metal oxides, as well as the considerable cycling stability. [99] The lithiation/ delithiation processes of the silica follow Equations 8 and 9: [100] SiO…”