Stress- and Interface-Compatible Red Phosphorus Anode for High-Energy and Durable Sodium-Ion Batteries

Abstract

Sodium-ion batteries are promising candidates for energy storage application, but the absence of high-capacity and low-cost anode materials significantly limits their practical specific energy and cost. Red phosphorus (RP) possesses a high theoretical specific capacity but suffers from large volume change, low electronic conductivity, and unstable solid-electrolyte interphase (SEI). Herein, a hierarchical micro/nanostructured antimony-doped RP/carbon anode was developed, which demonstrates extraordinary electrochemical performance with high initial Coulombic efficiency of ∼90%, high areal capacity (∼1.7 mAh cm −2 ), and good cycle stability and rate capability. Combined experimental and computational studies consistently revealed that such a unique structural design can dramatically accommodate the mechanical stress and moreover effectively restrain the undesired decomposition of electrolyte solvents regardless of electrolyte formulation, resulting in superior structural integrity and thin and robust SEI formation during cycling. The present finding has offered an alternative strategy for stress management and interface engineering on high-capacity alloying-based anode materials.

Hierarchical Ion/Electron Networks Enable Efficient Red Phosphorus Anode with High Mass Loading for Sodium Ion Batteries

“…To further illustrate the advantages of our designed high mass loading RP electrode, we compared the areal capacity versus areal current density of WDC/CNTs@RP‐8.2 mg cm −2 with some representative RP anodes reported recently. [ 17,18,22–30,37,51,52 ] As shown in Figure 4d and Table S1, Supporting Information, the WDC/CNTs@RP demonstrated the highest areal capacity at varied areal current densities compared to the previously reported RP anodes with different mass loadings, implying the superior redox reaction kinetics of the NaP chemistry in WDC/CNTs@RP electrode. Moreover, the WDC/CNTs@RP electrode can deliver a highly reversible areal capacity of 1.62 mAh cm −2 even at 106.6 mA cm −2 , which hasn't been reported in previous literatures.…”

Bi Works as a Li Reservoir for Promoting the Fast‐Charging Performance of Phosphorus Anode for Li‐Ion Batteries

“…[12,13] To solve these problems, various carbon carriers and conductive polymer coating layers are usually introduced into P anode. [1][2][3][14][15][16][17][18] However, high Li diffusion barriers in carbon-based frameworks (0.34 eV) [19] and the heterogeneous interface, respectively, hinder the superior fastcharging performance of P-based composites. In addition, the problem of uneven local reaction in P particles has not been solved yet.Herein, to enhance the fast-charging performance, we introduced electrochemically active bismuth, a 2D layered material with a layer spacing of 0.396 nm, [20,21] into P/graphite (P/C) composite as a functional filler by the ball-milling method.…”

“…[12,13] To solve these problems, various carbon carriers and conductive polymer coating layers are usually introduced into P anode. [1][2][3][14][15][16][17][18] However, high Li diffusion barriers in carbon-based frameworks (0.34 eV) [19] and the heterogeneous interface, respectively, hinder the superior fastcharging performance of P-based composites. In addition, the problem of uneven local reaction in P particles has not been solved yet.…”

Multiscale Understanding of Surface Structural Effects on High‐Temperature Operational Resiliency of Layered Oxide Cathodes

“…In our previous works, we have used this setup to reveal the volume changes of many alloying‐based anodes during (de) lithiation. [ 29–33 ] Here we further used it to understand how PEDOT coating help mitigate the intergranular cracking of NCM811 cathode during charge/discharge.…”

“…In our previous works, we have used this setup to reveal the volume changes of many alloying-based anodes during (de) lithiation. [29][30][31][32][33] Here we further used it to understand how PEDOT coating help mitigate the intergranular cracking of NCM811 cathode during charge/ discharge. Figure 4b shows the voltage-profiles of single bare and coated NCM811 particle during charge/discharge at 300 pA (≈C/10) within 2.7-4.5 V, similar to that in the coin-cell.…”