A Separator with Double Coatings of Li₄Ti₅O₁₂and Conductive Carbon for Li‐S Battery of Good Electrochemical Performance

Abstract

The market demand for energy pushes researchers to pay a lot of attention to Li-S batteries. However, the 'shuttle effect', the corrosion of lithium anodes, and the formation of lithium dendrites make the poor cycling performances (especially under high current densities and high sulfur loading) of Li-S batteries, which limit their commercial applications. Here, a separator is prepared and modified with Super P and LTO (abbreviation SPLTOPD) through a simple coating method. The LTO can improve the transport ability of Li + cations, and the Super P can reduce the charge transfer resistance. The prepared SPLTOPD can effectively barrier the pass-through of polysulfides, catalyze the reactions of polysulfides into S 2− , and increase the ionic conductivity of the Li-S batteries. The SPLTOPD can also prevent the aggregation of insulating sulfur species on the surface of the cathode. The assembled Li-S batteries with the SPLTOPD can cycle 870 cycles at 5 C with the capacity attenuation of 0.066% per cycle. When the sulfur loading is up to 7.6 mg cm −2 , the specific discharge capacity at 0.2 C can reach 839 mAh g −1 , and the surface of lithium anode after 100 cycles does not show the existence lithium dendrites or a corrosion layer. This work provides an effective way for the preparation of commercial separators for Li-S batteries.

A separator coated with commercial LiFePO4 and conductive carbon for Li–S battery with good cycling performance

“…S9†), afer 100 cycles of the cell with the SPLFPPD at 1C., and the surface of the cathode was porous. Compared with the cells with the LFPPD and the base separator (with a dense surface layer), 47 the porous structure is beneficial for the deep diffusion of polysulfides within cathodes. 37,47…”

“…Compared with the cells with the LFPPD and the base separator (with a dense surface layer), 47 the porous structure is beneficial for the deep diffusion of polysulfides within cathodes. 37,47…”

Facile one-pot synthesis of biomass-derived activated carbon as an interlayer material for a BAC/PE/Al2O3 dual coated separator in Li–S batteries

“…We conrmed that the good electrical conductivity by adding BAC layer could decrease the internal resistance, resulting in good electrochemical performances. [69][70][71] The rate performance of both types of coin cells was tested at various C-rate values from 0.1 to 2.0C and 0.1C again (Fig. 6(e)).…”

A strontium ferrite modified separator for adsorption and catalytic conversion of polysulfides for excellent lithium–sulfur batteries

“…31,32 Based on the foregoing, modifying the separator with bimetallic oxides and carbon materials is a potential strategy for improving electrochemical performance. 33,34…”