What is the working principle of lithium-sulfur batteries

The positive electrode of a lithium-sulfur battery is sulfur or a sulfur-containing material, and the negative electrode is lithium. The average voltage is 2.1V. In theory, the lithium-sulfur system (Li-S) has a specific capacity of 1672mAh/g and an energy density of 2600Wh/kg. It is a traditional commercial lithium-ion battery with LiCo02 as the positive electrode (theoretical specific capacity 273.8mAh/g , Energy density 360Wh/kg) about 7 times. Compared with ordinary lithium-ion batteries, the nature of the discharge of lithium-sulfur batteries is not simple lithium ion deintercalation, but a redox process accompanied by a large number of intermediate products. During the discharge process of lithium-sulfur discharge battery, elemental sulfur reacts with Li from ring-opening S8, and the conversion from long-chain Li2S8 to short-chain Li2S is accompanied by two obvious discharge platforms, the high-potential discharge platform is 2.45V-2.1 V, the process can be considered that a large amount of S8 is converted to S42-, while the low-potential discharge is 2.1V1.7V. This process is a large amount of S42- converted into S22- and S2-. On the other hand, different conversion degrees also correspond to different capacitances. The discharge reaction equation is as follows: positive electrode: S8+16Li+e-→8Li2S negative electrode: Li→Li++e-total reaction: 2Li+nS→Li2Sn→Li2S ordinary lithium ion battery is single-electron deintercalation, lithium-sulfur battery is 8 electrons Redox, which has 7-8 times the theoretical capacity and energy density. Similar to traditional lithium-ion batteries, lithium-sulfur batteries are composed of a positive electrode, a negative electrode, a separator, an electrolyte, and a separator. Therefore, lithium-sulfur batteries are considered to be the most promising alternative to traditional lithium-ion batteries and become a new energy source for a new generation of energy storage equipment. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: What should I pay attention to when using lithium-ion batteries?