Abstract: Fine water mist can effectively extinguish the fire in the lithium iron phosphate battery for energy storage power stations and inhibit battery re-ignition. However, the impact of water mist spray on neighboring normal batteries in a non-thermal runaway state during the fire extinguishing process has not been clear, which partly limits its popularization and application in the field of fire safety in the energy storage battery. This paper takes a 326 Ah normal LFP battery module as the test object to systematically studies the effect of continuous spraying of water mist on its safety and electric performances and data monitoring module (BMU) function. The experimental results show that the battery modules do not have the phenomenon of bulging, gas production, temperature rising, burning, electric spark, voltage fluctuate wildly, etc, and the BMU data collection function is normal during the 15min of continuous spraying of water mist and the subsequent observation period. In addition, there are no significant fluctuations in the charge-discharge performance of the battery packs before and after the water spray test. The results of this study verify the reliability of the water mist in the fire extinguishing process of the lithium iron phosphate energy storage battery modules.

Key words: energy storage power station, lithium iron phosphate battery, reliability, water mist