1 lithium ion power battery capacity decline mechanism

Ideal lithium ion battery, in addition to lithium ion embedding and out between is negative, no other side reactions, absence of lithium ion irreversible consumption. The actual lithium ion battery, every time there is side effect, also have the consumption of active substances irreversible. Many scholars at home and abroad of lithium manganese acid lithium ion battery capacity loss mechanism are studied, dreamman for various mechanisms are summarized. The cause of lithium ion battery capacity decline mainly include: the dissolution of the anode materials and phase change of the anode materials and electrolyte decomposition, charging, self-discharge, the formation of the interfacial film (SEI), set fluid corrosion, etc.

With a lithium manganese acid lithium ion power battery as an example, study the use of performance degradation data for power battery life prediction method. Study found that the battery capacity basically accords with power function decline trajectory, using the decay model extrapolation battery pseudo failure life; Pseudo failure life distribution was studied, the results of weibull distribution fitting effect is best, based on weibull lifetime distribution to evaluate the reliability of the battery. Analyzes practical cycle for life prediction of how much impact on the accuracy of the data. The life model and the reliability evaluation method has higher precision and solves the dynamic long battery life evaluation period and high cost problems.