Multifunctional Separator Enables High‐Performance Sodium Metal Batteries in Carbonate‐Based Electrolytes

Abstract

Sodium metal has become one of the most promising anodes for next‐generation cheap and high‐energy‐density metal batteries; however, challenges caused by the uncontrollable sodium dendrite growth and fragile solid electrolyte interphase (SEI) restrict their large‐scale practical applications in low‐cost and wide‐voltage‐window carbonate electrolytes. Herein, a novel multifunctional separator with lightweight and high thinness is proposed, assembled by the cobalt‐based metal–organic framework nanowires (Co‐NWS), to replace the widely applied thick and heavy glass fiber separator. Benefitting from its abundant sodiophilic functional groups and densely stacked nanowires, Co‐NWS not only exhibits outstanding electrolyte wettability and effectively induces uniform Na+ ion flux as a strong ion redistributor but also favors constructing the robust N,F‐rich SEI layer. Satisfactorily, with 10 µL carbonate electrolyte, a Na|Co‐NWS|Cu half‐cell delivers stable cycling (over 260 cycles) with a high average Coulombic efficiency of 98%, and the symmetric cell shows a long cycle life of more than 500 h. Remarkably, the full cell shows a long‐term life span (over 1500 cycles with 92% capacity retention) at high current density in the carbonate electrolyte. This work opens up a strategy for developing dendrite‐free, low‐cost, and long‐life‐span sodium metal batteries in carbonate‐based electrolytes.

Inhibition of sodium dendrites by solvent structural reorganization for non-flammable high-performance sodium-metal batteries

“…5d displays the N 1s spectrum, where a signal at 399.8 eV corresponding to N x O y − is observed only in the TEP-FB electrolyte due to the presence of the BSTFA additive, which is absent in the TEP-F electrolyte. 51 On the other hand, similar peak signals were observed in both electrolytes with Na–F (684.2 eV), P–F (687.3 eV), and NaF (1071.8 eV) signals being observed. 52 No significant signals were observed in the Si 2p spectra for both electrolytes (Fig.…”

Tertiary‐Amine Based Network Polymer Electrolyte for Improving the Cyclic Stability of Na Metal Batteries with Large Capacity

“…[ 31 ] As known, NaF has a high Young's modulus, which has the positive effect on the deposited morphology and cyclic stability of Na metal. [ 32,33 ] As shown in Figure S17 (Supporting Information), more NaF and less oxidic organic can be detected in the GPE(PBMP) derived SEI than that from LE(TEA). However, the contents of the N element show a huge difference.…”

Interfacial Spinel Local Interlocking Strategy Toward Structural Integrity in P3 Oxide Cathodes

“…Developing energy storage systems is an effective way to integrate these green sources. Among various strategies for storing energy, rechargeable batteries especially sodium-ion batteries (SIBs) are the most promising due to their low-cost and safe properties. − …”