Designing Conformal Electrode-electrolyte Interface by Semi-solid NaK Anode for Sodium Metal Batteries
Solid-state Na metal batteries (SSNBs),known for its low cost,high safety,and high energy density,hold a significant position in the next generation of rechargeable batteries.However,the urgent challenge of poor interfacial contact in solid-state electrolytes has hindered the commercialization of SSNBs.Driven by the concept of intimate electrode-electrolyte interface design,this study employs a combination of NaK alloy and carbon nanotubes to prepare a semi-solid NaK (NKC) anode.Unlike traditional Na anodes,the paintable paste-like NKC anode exhibits superior adhesion and interface compatibility with both current collectors and gel electrolytes,significantly enhancing the intimate contact of electrode-electrolyte interface.Additionally,the filling of SiO2 nanoparticles improves the wettability of NaK alloy on gel polymer electrolytes,further achieving a conformal interface contact.Consequently,the overpotential of the NKC symmetric cell is markedly lower than that of the Na symmetric cell when subjected to a long cycle of 300 h.The full cell coupled with Na3V2(PO4)2 cathodes had an initial discharge capacity of 106.8 mAh·g-1 with a capacity retention of 89.61％ after 300 cycles,and a high discharge capacity of 88.1 mAh·g-1 even at a high rate of 10 C.The outstanding electrochemical performance highlights the promising application potential of the NKC electrode.
Solid-state Na metal batteryNaK alloyGel electrolyteelectrode-electrolyte interfacedendrite free anode
国家科技期刊平台
NSTL
万方数据
