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The well‐matched technology of cathode and anode in Na‐ion full batteries is highly challenging yet critically important in practical applications. Here, the high‐performance Na‐ion full batteries are developed by using NaTi2(PO4)3/N‐doped mesoporous hard carbon hybrid anode and porous Na3V2(PO4)3 cathode. The different anodes are designed for well‐matched Na‐ion full batteries. The unique sandwich and mesoporous structural features endow the hybrid anode with a high reversible capacity (240 mAh g−1 at 1 C), high rate performance (109.7 mAh g−1 at 100 C), ultrahigh energy/power densities (76.56 Wh kg−1/5104 W kg−1) and a long cycle‐life (capacity retention of 92.1 % after 1000 cycles at 100 C) in a half cell. In a full battery this hybrid anode can also deliver a higher capacitive contribution (79.5–87.7 %) and high energy/power densities (104 Wh kg−1/5256 W kg−1). This design provides a promising pathway for developing high performance and low‐cost Na‐ion full batteries. [ABSTRACT FROM AUTHOR]

• TiO 2 nanosheets and RGO layers modify MoS 2 layers to realize porous hierarchical. • The porous hierarchical architecture improves electrons and ions transport for SIBs. • The synergistic effect among TiO 2 , MoS 2 and RGO improves electrochemical performance. To enhance the reversible capacity and cycle stability of MoS 2 as anode materials for sodium ion batteries (SIBs), we constructed a hybrid architecture composed of MoS 2 and TiO 2 nanosheets, linking with reduced graphene oxide (RGO) to another TiO 2 /MoS 2 to form a nanoflower structure. Owing to layered RGO coupled with TiO 2 /MoS 2 hybrid, such a composite offered interconnected conductive channels to short shuttle path of Na+ ions and favorable transport kinetics under charge/discharge cycling. Moreover, this unique structure showed a porous and hierarchical architecture, which not only buffered volume changes but also provided more electrochemical active sites during insertion/deintercalation processes of Na ions. Outstanding electrochemical performances were identified by the component matching effect among TiO 2 , MoS 2 and RGO with a three-dimensional (3D) interconnected network, exhibiting a good reversible capacity of 616 mA h g−1 after 100 cycles at 0.1 A g−1, an excellent rate capability of 250 mA h g−1 even at 5A g−1 and a long cycling stability of 460 mA h g−1 with a capacity fluctuation of 0.03% per cycle within 350 cycles at 1 A g−1. [ABSTRACT FROM AUTHOR]

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 NaSn 2 (PO 4) 3 submicro-particles (around 100–300 nm in size) by hydrothermally assisted pyrolysis reactions. The synthesized NaSn 2 (PO 4) 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. Image 1 • NaSn 2 (PO 4) 3 submicro-particles are synthesized by hydrothermally assisted pyrolysis reactions. • The submicro-particle anode exhibits an ultrahigh discharge capacity of 1868.5 mAh g−1 at 0.1 A g−1. • This anode has excellent cycling stability (capacity retention of 106% after 200 cycles at 5 A g−1). • The synthesis mechanism of NaSn 2 (PO 4) 3 submicro-particles is evaluated. [ABSTRACT FROM AUTHOR]

The development of sodium-ion batteries with high power density is highly challenging yet critically important in many applications. Herein, we develop sodium-ion batteries with ultrahigh power density by using N-doped hard/soft double-carbon-coated Na 3 V 2 (PO 4) 3 hybrid-porous microspheres as a cathode. A higher working potential of 3.4 V, superior rate capability (93 mA h g−1 at 10C, 81 mA h g−1 at 30C) as well as stable cycling performance (72.9% capacity retention at 10C after 1000 cycle) are simultaneously achieved. Very impressively, it can deliver pseudocapacitive behavior and a practical energy density of 317 W h kg−1 at a power density of 194 W kg−1, which also remains 73.5 W h kg−1 even at an ultrahigh power density of 12600 W kg−1. The superior performances can be ascribed to the hybrid-porous microsphere structure, which provide favorable kinetics for bath electron and Na+, large cathode-electrolyte contact area, as well as robust structural integrity. This design provides a promising pathway for developing low-cost sodium-ion batteries with high energy density as well as high power density. Image 1 • N-doped hard/soft double- carbon-coated Na 3 V 2 (PO 4) 3 hybrid-porous microspheres were synthesized. • The EN/EG mixed solution controlled the formation of the hybrid-porous microspheres. • The microsphere cathode shows superior rate capability and high energy density. • ►It also exhibits ultrahigh power density due to pseudocapacitive behavior. [ABSTRACT FROM AUTHOR]