Progress on thermal runaway propagation characteristics and prevention strategies of lithium-ion batteries

Abstract

<p indent="0mm">lithium-ion batteries have been widely used in energy storage systems due to their significant advantages such as relatively high energy and power density. In order to meet the capacity and voltage requirements of the energy storage system, it is necessary to connect the battery monomer to form a module or even a battery pack through different configurations. For the battery system composed of a large number of batteries, which is a vast reservoir of energy, its safety should be considered from the perspective of the energy storage system to ensure long-term safe and reliable operation. Because of the high energy density, flammable electrolyte and low stability of the separator, batteries may get into the problem of thermal runaway. If the speed of the thermal runaway propagation cannot be well controlled in the local area, thermal runaway could propagate from one initiating battery to its neighbors and cause disastrous consequences at the system level. Therefore, when the battery system fails to make key breakthroughs and the intrinsic safety problems cannot be fundamentally solved, it is particularly important to prevent thermal runaway propagation effectively. The purpose of this review is to discuss the research progress on thermal runaway propagation characteristics and prevention strategies of lithium-ion batteries. Firstly, the abuse conditions that may lead to thermal runaway are summarized. Then the characteristics of thermal runaway propagation are clarified from the perspectives of electrical characteristic and heat transfer characteristic. To further describe the heat transfer process of thermal runaway propagation, the thermal network diagram of the battery module is established, which could provide theoretical support for the design of the prevention strategies for thermal runaway. Finally, the modeling method of battery thermal runaway is discussed, and a systematic review of prevention strategies is presented in terms of heat dissipation and insulation, phase change material technology, and the strategy taking into account the normal working conditions. For the heat dissipation and insulation strategy, it should be noted that in order to prevent thermal runaway propagation successfully, the simple heat dissipation method requires additional investment, including cost, space, power consumption, etc. While the effective heat insulation between batteries could help block the harmful heat transfer path and reduce the requirement of fast heat dissipation capacity. For the phase change material technology, the heat transfer path diagram of the battery module is established. By improving the thermal conductivity of phase change material, the generated heat of the battery in case of thermal runaway could be distributed more uniformly to the phase change material in other areas of the module. Besides, the heat transfer capacity of the system can be further improved by setting heat transfer components at the module boundary or between the phase change materials. To further optimize the thermal management performance of the battery, the strategy taking into account the normal working conditions should be considered, which can meet the dual requirements of thermal safety and temperature control through a reasonable combination of heat conduction and insulation. This review is expected to provide theoretical basis and engineering application guidance in designing the thermal management system, so as to improve the safety performance of lithium-ion battery.