What factors affect the storage performance of lithium battery packs?

The structure of a lithium battery is composed of a positive electrode, a negative electrode, an electrolyte, a separator, and a casing. (1) The formation of the irreversible capacity of the negative electrode is that as the storage time increases, part of the lithium embedded in the graphite layer of the negative electrode loses its activity and becomes dead lithium, which cannot be discharged back to the positive electrode. The formation of these dead lithium affects the capacity change. The impact is negative, so with the increase of SOC, the more capacity will be lost because of this reason; (2) According to Ohm's law: Uu003dUR+Uru003dI(R+r), where: U is the battery Electromotive force; UR is the circuit terminal voltage; Ur is the battery internal consumption voltage; R is the external circuit resistance; r is the internal resistance of the battery; I is the discharge current. Due to the increase in internal resistance during the shelving process; the increase in the terminal voltage decreases, the terminal voltage arrives earlier during discharge, and the discharge time is reduced compared to the initial storage period, which reduces the discharge capacity. This effect is also negative; (3) ) With the prolonged storage time of the positive lithium iron phosphate battery pack, the secondary particle particles cracked, forming a clean interface, and regaining the activity of deintercalating lithium ions. This effect is positive. Therefore, the increase in capacity may be present. Early stage of storage. By detecting the changes in battery performance such as AC internal resistance, capacity, DC internal resistance, and power capacity of the 48V lithium battery pack after being placed at different temperatures and different SOCs, it is found that the changes in various properties of the battery are different during the process of shelving. In the actual storage of the battery, suitable storage conditions should be selected according to the length of storage time and the direction of use of the battery. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete it.