Multi-functional stainless steel composite frames stabilize the sodium metal battery

Abstract

The sodium (Na) metal battery has the prospect of promising high energy density and sustainable technology for low-cost energy storage. However, the soft texture and high reactivity of Na cause it easy to structure collapse and produce side reactions with organic electrolytes. Inspired by ancient Chinese architecture, a structural engineering strategy is introduced to conquer the above issues. PVDF film-covered stainless steel mesh (SMPF) embedded in the obverse of Na metal to form a “self-limiting” Na/electrolyte interface and bare stainless steel mesh (SM) with high electronic conductivity embedded in the reverse of Na metal to form a uniformly electronic distributed Na/collector interface. Based on the electric field simulation and in-situ optical tests, the well-designed structure of the SM@Na@SMPF electrode can restrict the dendrite growth and slow down the bubbles release. The above strategies provide important technical support for the large-scale application of flexible Na metal batteries.