The composition and working principle of lithium-ion battery

Source: 2020 - 03 - Then hits: 30 composition and working principle of the solid sulfur is a kind of S8 ring in yellow. Lithium sulfur batteries of high energy density and high specific capacity is due to the S8 s - in the molecule S key fracture and recombine. At present, the positive data of the lithium sulfur batteries are mostly by porous carbon data with the sulfur, carbon nanotubes, graphene, metal oxide and conducting polymers such as combination, while the negative data is obtained by lithium tablets. The electrochemical reaction mechanism of lithium sulfur batteries: the S8 + 16 li2 & rarr; 8Li2S。 In the process of discharge, lithium metal anode ( Cathode) Was oxidized to form lithium ions and electrons. Lithium ion to the cathode through the electrolyte mobile, electronic through an external circuit leads to the cathode ( The anode) 。 Sulfur in the anode, and lithium sulfide lithium ions and electrons reaction. The process of charging the opposite. From the perspective of the reflection process, the discharge process of detailed, the first lithium sulfur formed a series of long chain center lithium sulfide ( S8→ ) Li2S8→ Li2S6→ Li2S4) The long chain material easy dissolve in ether electrolyte, long chain of residual sulfur in 25% of the total capacity. When the rest of the sulfur further lithification, dissolve the long chain of polysulfide is decomposed into short chains of sulfide ( Li2S4→ Li2S2→ Li2S) 。 Solubility of lithium sulfide is insufficient, form some solid matter deposition on the electrode. In this process, the sulfur accounted for 75% of the total sulfur. To sum up, along with the discharge process of lithium sulfur batteries inside the raw material, through the solid - Liquid - Solid three conditions of transformation, and the traditional lithium-ion batteries in the discharge process is mainly lithium ion transport is very different.