Sponge‐Like Porous‐Conductive Polymer Coating for Ultrastable Silicon Anodes in Lithium‐Ion Batteries

Abstract

Urgent calls for reversible cycling performance of silicon (Si) requires an efficient solution to maintain the silicon‐electrolyte interface stable. Herein, a conductive biphenyl‐polyoxadiazole (bPOD) layer is coated on Si particles to enhance the electrochemical process and prolong the cells lifespan. The conformal bPOD coatings are mixed ionicelectronic conductors, which not only inhibit the infinite growth of solid electrolyte interphase (SEI) but also endow electrodes with outstanding ion/electrons transport capacity. The superior 3D porous structure in the continuous phase allows the bPOD layers to act like a sponge to buffer volume variation, resulting in high structural stability. The in situ polymerized bPOD coating and it‐driven thin LiF‐rich SEI layer remarkably improve the lithium storage performance of Si anodes, showing a high reversible specific capacity of 1600 mAh g−1 even after 500 cycles at 1 A g−1 along with excellent rate capacity of over 1500 mAh g−1 at 3 A g−1. It should be noticed that a long cycle life of 800 cycles with 1065 mAh g−1 at 3 A g−1 can also be achieved with a capacity retention of more than 80%. Therefore, we believe this unique polymer coating design paves the way for the widespread adoption of next‐generation lithium‐ion batteries.

In Situ Copper Coating on Silicon Particles Enables Long Durable Anodes in Lithium-Ion Batteries

“…Figure d portrays the rate performance of the HT-Si@Cu-0.08 electrode, revealing specific discharge capacities of 1228, 1137, 1022, and 846 mA h g –1 at current densities of 0.2, 0.5, 1, and 2 A g –1 (correspond to Figure S7c), respectively. When the current density changed from 2.0 to 0.2 A g –1 , the HT-Si@Cu-0.08 electrode was still able to exhibit a specific capacity of 1236 mA h g –1 , revealing its excellent electrochemical stability (the increasing capacity can be attributed to the activation of electrode materials in the initial cycles).…”

Constructing a Stable Integrated Silicon Electrode with Efficient Lithium Storage Performance through Multidimensional Structural Design

“…Notably, I1 exhibits a relatively high presence of LiF on its surface, which promotes the transport of Li + and enhances the lithiation/delithiation kinetics process. 37,65 The contents of the N and Si elements are relatively low in all four electrodes, but the signal of Si in I1 stands out significantly, suggesting a relatively thin SEI film. Furthermore, Figure S15e−h provides additional evidence for the commendable structural integrity of SiNW in I1 after 20 cycles, indicating a smaller volume change compared to the other electrodes.…”

Acid- and Alkali-Resistant Microporous Na4Cu8Ge3S12·xH2O Exhibiting Fast Mixed Sodium Ion and Electron Conduction

“…Mixed ion-electron conductors (MIECs), characterized by their ability to simultaneously transport ions and electrons, have critical applications in a wide range of electrochemical devices, including solid oxide fuel cells (SOFCs), − metal ion batteries, − sensors, − supercapacitors, electrochemical transistors, , and surface switching devices . Meanwhile, the unique dual conducting capability has sparked significant scientific interest in exploring preferable MIECs with high conductivity and good stability.…”

“…L SR (4) where L denotes the thickness of the sample, R represents resistance, and S signifies the cross-sectional area. When the temperature was increased further from 348 to 383 K, the measurements were performed to accurately determine the electronic conductivity of NCGS at different temperatures and relative humidities.…”