In Situ Construction of a Liquid Film Interface with Fast Ion Transport for Solid Sodium-Ion Batteries

Abstract

Solid sodium-ion batteries (SSIBs) are considered as one of the promising energy storage systems because of their high safety and high energy density. However, the sodium metal anode presents poor wettability with a solid electrolyte, resulting in high interface impedance and dendrite growth, which severely limits their application in practice. Herein, a novel liquid film (Na-BP) interface is constructed between sodium and solid electrolyte (Na 3 Hf 2 Si 2 PO 12 ) with an excellent kinetic mass transfer ability and good fluidity, which could guarantee a close contact and fast charge transfer at interface. The symmetric cells with the designed interface show a high-rate and long-cycle performance and could cycle stably more than 1000 and 700 h at 0.2 and 0.5 mA cm −2 , respectively. The critical current density of the cells can reach 3.6 mA cm −2 at room temperature, which is the highest value in similar works.

Optimization Strategies Toward Functional Sodium‐Ion Batteries

“…[89] Separator/electrolyte/SEI engineering is the commonly adopted methods to hinder dendrite growth and short circuiting. [129][130][131][132][133] Viscous electrolyte, thicker separator, and stable SEIs can mitigate the dendrite growth and thus avoid short circuits.…”

Inorganic All‐Solid‐State Sodium Batteries: Electrolyte Designing and Interface Engineering

“…[168] For example, Meng et al constructed in situ a novel liquid film interlayer between Na anode and solid electrolyte (Na 3 Hf 2 Si 2 PO 12 ) (Figure 10a). [169] This unique liquid interlayer not only improves interface wettability, but also helps guarantee a close contact between anode and electrolyte during repeated volume expansion/contraction of Na metal. The symmetric cells equipped with the liquid interlayer exhibited stable cycling performance (more than 1000 h and 700 h at the current densities of 0.2 and 0.5 mA cm −2 , respectively), and a critical current density reached 3.6 mA cm −2 at RT.…”

Recent advances in solid‐state metal–air batteries

“… 82 Thus, it is vital to take actions to protect the Na metal anode to improve battery lifespan. The construction of highly sodiophilic interfaces is a common improvement strategy 83,84 …”

“…The construction of highly sodiophilic interfaces is a common improvement strategy. 83,84 Based on theoretical calculations, Lu et al 83 chose 1 M NaClO 4 /fluoroethylene carbonate to treat Na metal anode, and the generated NaF-rich interlayer (8 nm) could effectively promote Na + transport and reduce interfacial resistance (Figure 6B). In addition, it should be noted that oxygen crossover from the air to the Na metal anode may cause irreversible damage in Na-air batteries, and choosing a dense electrolyte to block oxygen crossover is necessary.…”