Study on the criticality of thermal safety of cylindrical battery

In view of the complexity of the storage environment in the process of storage and transportation, typical storage environment of cylindrical battery was analyzed in this paper. The corresponding three-dimensional thermal explosion models were established which considering non-uniform heat dissipation of the lateral surface and different heat dissipation of top and bottom surfaces. Based on the seven-point difference method and Newton–homotopy method, calculation algorithm and program of partial differential equation group have been established and verified. The influence of H and Biot on the criticality of system was analyzed. The results of a kind of cylindrical battery which stored in two typical environments (shelf and ground) were obtained by the calculation program. The critical thermal explosion ambient temperature of cylindrical battery is, respectively, 568.0 and 566.6 K. When the ambient temperature is 575 K, the thermal explosion time to ignition is, respectively, 1.504 (5194.7 s) and 1.596 (5512.1 s).