Foldable anode-free sodium batteries enabled by N,P-codoped carbon macroporous fibers incorporated with CoP nanoparticles

Anode-free sodium batteries (AFNBs) are regarded as promising alternatives for next-generation energy storage systems because of their high energy density, high safety, cost-effectiveness, and simple manufacturing processes. However, their practical application is limited by a low coulombic efficiency (CE) and a short lifespan resulting from a large volume change and the growth of Na dendrites. Here, we propose a three-dimensional versatile host composed of interconnected N,P-codoped carbon macroporous fibers incorporated with CoP nanoparticles (denoted as CoP@N/P-CMFs) for selective nucleation and uniform deposition of Na. The porous skeleton reduces structural stress and inhibits dendrite growth by…