Font Size: 

The lithium/sulfur battery has been attracting increasing attention due to their higher theoretical specific energy density (2,600 Wh kg⁻¹), almost ten times greater than that of commercially used lithium ion batteries. However the practical energy density of the Li/S battery (soft package) is still low, accompanied other unsolved problems as poor cycle life, low safety as well as worse rate capability. In order to solve these problems, we need to develop better cathode materials, better electrolyte composition, better anode protect mechanism and ect.

In our lab, we mainly focus on the study of cathode materials (carbon/sulfur), cathode structure, electrolyte and separators, which are combined together to improve the battery performance. For one thing, by improving the cathode (including the carbon surface area, C/S ratio, porous distribution), the energy density of the Li/S battery has been improved to 440 Wh/kg (discharge to 1.9 V) in our lab.

For another thing, by improving the electrolyte and separator, the Li/S coin cell could cycle 100 cycles with capacity retention of 70% (still over 800mAh/g (S)) with 3.0 mg/cm² (S) cathode. In this presentation, the development of Li/S battery in the energy storage department of Dalian Institute of Chemical Physics will be introduced, including materials design (cathode and electrolyte), preparation and soft package design. Battery performance with different carbon materials combined with different electrolyte series will be discussed in detail.