Abstract: A study on the fire suppression characteristics of lithium iron phosphate energy storage battery modules during the early stage of thermal runaway was conducted based on a micro fire suppression module. The module was filled with a ternary mixed fire extinguishing agent developed in earlier research by the project team. The experiment used overheating as the trigger condition and obtained key parameters such as temperature rise during battery venting and thermal runaway, critical temperatures, and fire suppression behavior characteristics, which can provide guidance for fire prevention in energy storage battery packs. The micro temperature-sensitive automatic fire suppression module can extinguish the initial fire of a lithium iron phosphate energy storage battery module during thermal runaway within 3 seconds. If no ignition sources such as open flames or electric sparks are present, the battery fire does not reignite. By pre-installing micro fire suppression modules in energy storage battery packs, fire protection can be provided during transportation, installation, and other scenarios where effective safety measures are unavailable.

Key words: energy storage, lithium-iron phosphate battery, thermal runaway, battery fire, fire suppression effect