Deformation and fracture of battery without CFRP layer During TR, the battery shell swells due to the increase of internal pressure P and temperature T. The deformation ε consists of two parts: the deformation ε p produced by internal pressure and the deformation ε t introduced by the thermal expansion effect.
The deformation ε consists of two parts: the deformation ε p produced by internal pressure and the deformation ε t introduced by the thermal expansion effect. The simulation results show that the stress concentration first occurs in the bottom edge of the battery (Fig. 7 a and c).
Battery degradation occurs due to ageing mechanisms in its components and increases in internal resistance. It is collectively under-pinned by irreversible chemical and structural changes in battery components. Capacity fade is a gradual decrease in the amount of charge a battery can hold and occurs with repeated use as the battery ages.
Deformation and fracture of battery under different temperature distributions According to the experimental observations, there are various fracture behaviors (such as shapes and positions of the facture) of the cell shell during TR which can be classified into two types, i.e., end (or cap) rupture and side rupture.
However, there are numerous chemical, electrochemical and physical processes that occur during operation of the battery that can lead to incomplete charge/mass transfer. This invariably results in degradation and eventual failure – a process that happens more rapidly if the battery is subjected to repeated fast charging.
An internal short circuit occurs when the two electrodes in a battery cell become electronically connected. The resulting high current density can give rise to localised temperature increases, and in certain circumstances a thermal runaway. Lithium iron phosphate (LiFePO 4) is a cathode material used in LIBs.