Boosting Cyclability and Rate Capability of SiO_x via Dopamine Polymerization-Assisted Hybrid Graphene Coating for Advanced Lithium-Ion Batteries

Abstract

SiO x suffers from the 200% volume change during cycling and low electronic conductivity, resulting in poor cyclability and rate capability as a lithium-ion battery anode. Herein, we demonstrate a dopamine polymerization-guided carbon coating for SiO x anodes (SiO x @PDA@GNH). SiO x @PDA@GNH delivers charge capacities of 1269 and 1140 mA h·g–1 at charge rates of 0.05 and 3 C, respectively, and a capacity retention of 79.60% after 150 cycles at 1 C. A full cell with LiNi0.8Co0.1Mn0.1O2 or cathode demonstrates a capacity retention of >80% after 100 cycles at the rate of 0.33 C with an area capacity over 3.2 mA h·cm–2. Suppressed crack and overgrowth of the SEI layer are the key contributions for the improved performance. These results enlighten a practical pathway for the designing and modifications of SiO x anodes for high energy density lithium-ion batteries.

Rational design of SiOx based anode materials for next generation lithium-ion batteries

“…Gu et al 78 demonstrated a simple way to coat SiO x with polydopamine (PDA) with rich hydroxyl groups; PDA is able to form a stable carbon layer on the surface of SiO x (SiO x @PDA@GNH). The functional groups on dopamine can bond with the graphene nanotube hybrid (GNH) to form a hybrid layer, and the coating layer is evenly distributed and has good electrolyte wetting properties.…”

“…Overgrowth and suppressed cracking of the SEI layer are considered crucial factors that significantly impact performance, and the tight coating of SiO x with the carbon layer avoids contact between SiO x and the electrolyte, thus forming a stable SEI film to enhance the cycle performance. Gu et al 78 demonstrated a simple way to coat SiO x with polydopamine (PDA) with rich hydroxyl groups; PDA is able to form a stable carbon layer on the surface of SiO x (SiO x @P-DA@GNH). The functional groups on dopamine can bond with the graphene nanotube hybrid (GNH) to form a hybrid layer, and the coating layer is evenly distributed and has good electrolyte wetting properties.…”

Insights into Enhancing Electrochemical Performance of Li-Ion Battery Anodes via Polymer Coating

“…This composite anode demonstrated a specific capacity of about 1120 and 417 mAh g −1 after 500 cycles at 1.0 and 16.5 A g −1 , respectively. PDA coating on SiO x developed by Gu et al [112] showed better wetting properties with water and electrolyte solution. It delivered an initial Columbic efficiency of 80.48% and excellent specific capacities of about 1270 and 1140 mAh g −1 at 0.05 and 3 C, respectively, and a capacity retention of about 80% after 150 cycles at 1 C.…”

Encapsulating biomass-derived SiOx with internal conductive channels in nitrogen-doped flexible carbon cages for high performance Li ion-battery anodes

“…13,14 However, pure SiO x materials also suffer from some drawbacks, such as low conductivity and inevitable volume expansion (≈200%). 15 Many strategies have been proposed to solve the above mentioned problems, such as SiO x /C composites, [16][17][18] constructing SiO x nanostructures, 19 and the optimization of conductive agents and binders. 20,21 However, SiO x can hardly be applied on a large scale because of the lack of mature raw materials and desirable structural design with both good mechanical strength and ion/electron transport pathways.…”