This review provides essential features of sulfide solid electrolytes and an in-depth explanation of the interface issues in all-solid-state lithium secondary batteries.
Glass-ceramic
sulfide solid electrolytes like Li7P3S11 are practicable propellants for safe and high-performance
all-solid-state lithium–sulfur batteries (ASSLSBs); however,
the stability and conductivity issues remain unsatisfactory. Herein,
we propose a congener substitution strategy to optimize Li7P3S11 as Li7P2.9Sb0.1S10.75O0.25 via chemical bond and
structure regulation. Specifically, Li7P2.9Sb0.1S10.75O0.25 is obtained by a Sb2O5 dopant to achieve partial Sb/P and O/S substitution.
Benefiting from the strengthened oxysulfide structural unit of POS3
3– and P2OS6
4– with bridging oxygen atoms and a distorted lattice configuration
of the Sb–S tetrahedron, the Li7P2.9Sb0.1S10.75O0.25 electrolyte exhibits prominent
chemical stability and high ionic conductivity. Besides the improved
air stability, the ionic conductivity of Li7P2.9Sb0.1S10.75O0.25 could reach 1.61
× 10–3 S cm–1 at room temperature
with a wide electrochemical window of up to 5 V (vs Li/Li+), as well as good stability against Li and Li–In alloy anodes.
Consequently, the ASSLSB with the Li7P2.9Sb0.1S10.75O0.25 electrolyte shows high
discharge capacities of 1374.4 mAh g–1 (0.05C, 50th
cycle) at room temperature and 1365.4 mAh g–1 (0.1C,
100th cycle) at 60 °C. The battery also presents remarkable rate
performance (1158.3 mAh g–1 at 1C) and high Coulombic
efficiency (>99.8%). This work provides a feasible technical route
for fabricating ASSLSBs.
All-solid-state lithium–sulfur
batteries (ASSLSBs) have
become a promising candidate because of their high energy density
and safety. To ensure the high utilization and electrochemical capacity
of sulfur in all-solid-state batteries, both the electronic and ionic
conductivities of the sulfur cathode should be as high as possible.
In this work, an intercalation–conversion hybrid cathode is
proposed by distributing sulfur evenly on electroactive niobium tungsten
oxide (Nb18W16O93) and conductive
carbon nanotubes (CNTs) for achieving high performance ASSLSBs. Herein,
Nb18W16O93 shows good electrochemical
lithium storage in the hybrid cathode, which could serve as an effective
Li-ion/electron conductor for the conversion of sulfur in the discharge/charge
processes to achieve a high utilization of sulfur. However, CNTs could
further increase the electronic conductivity of the hybrid cathode
by constructing good conductive frameworks and suppress the volumetric
fluctuation during the interconversion of sulfur and Li2S. With this strategy, the S/Nb18W16O93/CNT cathode achieves a high sulfur utilization of 91% after one
cycle activation with a high gravimetric capacity of 1526 mA h g–1. In addition, excellent rate performance is also
obtained at 0.5 C with a reversible capacity of 1262 mA h g–1 after 1000 cycles. This work offers a new perspective to develop
ASSLSBs.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.