The first charge capacity of the half battery is significantly lower than the first discharge capacity, that is to say, lithium ions in the process of discharge came to the graphite layer, and did not 100% from the graphite in the subsequent charge. What happens to the lithium ions that are lost? Those of you who believe that you have a certain theoretical basis can think of this reason: When the graphite half battery is discharged for the first time, the lithium ions will form SEI film on the surface of the graphite before embedding in the graphite, and the lithium ions dedicated to the SEI film cannot return to the negative electrode of the lithium sheet during the subsequent charging. PTMS LITHIUM COBALT ACID MATERIAL MAGNETIC resulting in graphite half battery first discharge capacity > first charge capacity.
For the PTMS LITHIUM COBALT ACID MATERIAL MAGNETIC, such as ternary anode materials, the main reason for the first efficiency is that the structure of the material changes after the first delithium, forming 100% lithium ion embedded back. For carbon negative electrode, the primary efficiency is mainly caused by SEI formation.
For the graphite or intermediate anode materials commonly used at present, the first efficiency is generally between 90 and 92%. For lithium titanate, which almost never forms SEI film, the first efficiency will be significantly improved, about 97%. In addition, for the current emerging silicon carbon anode materials, PTMS LITHIUM COBALT ACID MATERIAL MAGNETIC removal of iron is required. Because the first efficiency of silicon negative electrode is only 50%, the first efficiency of silicon carbon negative electrode will gradually decrease with the increase of silicon content.
Contact: DELLA
Mob: +86-13929907491
