A Monolithic Solid-State Sodium–Sulfur Battery with Al-Doped Na3.4Zr2(Si0.8P0.2O4)3 Electrolyte

LU, LIANG; LU, YAO; ALONSO, JOSÉ ANTONIO; LÓPEZ, CARLOS ALBERTO; FERNÁNDEZ-DÍAZ, MARIA TERESA; ZOU, BINGSUO; SUN, CHUNWEN

ACS APPLIED MATERIALS & INTERFACES

AMER CHEMICAL SOC

Lugar: Washington; Año: 2021

1944-8244

The limit of the energy density and increasing security issueson sodium-ion batteries (SIBs) impede their further development. Solid-statesodium metal batteries are potential candidates to replace the present SIBs.However, low ionic conductivity and poor interface contact hinder theirprogress. In this work, the impact of Al doping on the crystalline structure andionic transport in Na3.4Zr2(Si0.8P0.2O4)3 was studied by neutron powderdiffraction. The ionic conductivity of Na3.5Zr1.9Al0.1Si2.4P0.6O12 achieves 4.43× 10−3 S cm−1 at 50 °C. The polarization voltage of the Na||Na symmetricbattery is about 40 mV after cycling for more than 1600 h. Moreover, a solidstate sodium−sulfur battery with a monolithic structure was constructed toalleviate the interfacial resistance problems. Its specific discharge capacity canstill keep 300 mA h g−1 after 480 cycles at 300 mA g−1. The work provides apromising strategy to design solid-state sodium−sulfur batteries with highperformances.