Introduction, History, Advantages and Main Problems in Lithium/Sulfur Batteries Systems

Lithium/sulfur (Li/S) batteries have received a lot of interest as a possible alternative to traditional lithium-ion batteries because of their high energy density and low cost. This chapter provides an overview of the history, benefits and major issues associated with Li/S batteries. The historical background of Li/S batteries dates back to the 1960s, when researchers recognized the high specific capacity of sulfur as a cathode material. Since then, significant progress has been made to improve the performance and stability of Li/S batteries. In fact, 1980s marked the beginning of experimental work, followed by intensive research efforts in the 1990s to understand fundamental electrochemical processes and develop new materials and designs. In this chapter, we have highlighted the advantages of Li/S batteries are highlighted, in particular their high energy density. Sulfur, the cathode material, has a high theoretical capacity, allowing Li/S batteries to store more energy per unit mass compared to conventional lithium-ion batteries. This characteristic makes Li/S batteries attractive for applications requiring long-lasting power. In addition, the abundance and low cost of sulfur contribute to the profitability of Li/S batteries. In terms of environmental friendliness, sulfur is non-toxic and reduces reliance on environmentally sensitive materials, making Li/S batteries more durable. Despite their advantages, Li/S batteries face several challenges. One of the main issues is the dissolution of sulfur and the formation of polysulfide intermediates during cycling, which can lead to capacity loss and decreased battery performance over time. Researchers focused on solving this problem by developing sulfur hosts, confining sulfur in nanoscale structures, and optimizing electrolyte compositions. Another challenge is the volume expansion of sulfur during charge/discharge cycles, which can lead to electrode degradation and reduced life. In addition, the problems related to the low electrical conductivity of sulfur and the shuttle effect of polysulfides must be solved for the commercial viability of Li/S batteries.