Battery failure reason in detail?

Lithium ion battery failure and failure mechanism

Attenuation: (1) the capacity of ion battery capacity attenuation main points and reversible capacity attenuation and irreversible capacity attenuation. The reversible capacity attenuation can be used by adjusting the battery charging and discharging system and to improve environment and so on measures to restore the loss of capacity; And the irreversible capacity attenuation is irreversible change inside the irreversible capacity loss. Battery capacity attenuation failure is rooted in material, at the same time and the battery manufacturing process, use of environment and other objective factors have a close contact. From the material point of view, the main failure reason are the anode material of structure failure, and the cathode surface SEI hypertrophy, electrolyte decomposition and metamorphism, set fluid corrosion, system trace impurities, etc.

(2) the internal resistance increases, lithium ion battery internal resistance and battery system internal electronic transmission and ion transport process, mainly divided into the ohmic resistance and the polarization resistance, the polarization resistance is mainly caused by electrochemical polarization, electrochemical polarization and concentration polarization. Lead to the main factors of lithium ion battery internal resistance increases key material into the battery and battery using the environment. University of science and technology of China JueYongChun using synchrotron radiation technology such as jumping mechanism of transition element is potential delay and the cause of the voltage decay: shows inside the battery system, the key materials of anomaly is the basic factors affecting resistance increased and the cell polarization.

(3) the short circuit, short circuit performance can be divided into: 1) the short circuit between the copper/aluminum set fluid; (2) the diaphragm failure without electrical insulation or gap become ambassador of positive and negative micro contact, appear serious local fever, further charge and discharge process, may spread to all around, the formation of thermal runaway; (3) transition metal impurities in the anode paste did not remove clean, pierced diaphragm, or allowing the lithium cathode dendrite formation cause short circuit; (4) lithium dendrite lead to internal short circuit. In addition, the design and manufacture of the battery or battery pack assembly process, unreasonable design and local stress can also lead to internal short circuit.