NaSn2(PO4)3 submicro-particles for high performance Na/Li mixed-ion battery anodes

NaSn2(PO4)3 has open framework, high ionic conductivity, low working potential, high theoretical capacity more than twice of graphite. However, its commercial application is limited by its low electrical conductivity and rapid capacity fading. To overcome this challenge, we synthesize NaSn2(PO4)3 submicro-particles (around 100–300 nm in size) by hydrothermally assisted pyrolysis reactions. The synthesized NaSn2(PO4)3 anode for Na/Li mixed-ion batteries delivers an ultrahigh initial discharge capacities, excellent rate performance and superior cycling stability. This design provides a promising pathway for developing high performance mixed-ion batteries.