EFFICIENCY OF USING PORTABLE FIRE EXTINGUISHERS WHEN EXTINGUISHING LITHIUM-ION BATTERIES

Abstract

The article substantiates the trends in using electric energy storage systems consisting of a battery, an inverter, connecting conductors, safety automation, and, if necessary, solar panels. Such systems typically use lithium-ion batteries because of several technical advantages: high specific energy capacity, high discharge-charging currents, and many charge-discharge cycles, i.e., longevity. The chemical and electrochemical reactions that occur during the charge-discharge cycles of lithium-ion batteries can lead to irreversible electrothermal processes. Such processes cause an uncontrolled increase in temperature, the release of hazardous gases, fires, and explosions, often accompanied by fire. Therefore, the authors conducted a successful full-scale field study of the effect of various extinguishing agents of the most common portable fire extinguishers in Ukraine on the efficiency of extinguishing lithium-ion batteries. Based on the experiment, we found that extinguishing the lithium-ion module using a portable carbon dioxide fire extinguisher is the least effective among the extinguishers studied, with the resumption of flame combustion occurring within 3–4 s after the cessation of carbon dioxide supply to the combustion centre. When using a portable powder fire extinguisher, the flame combustion of the test module resumed after 18–20 s. The desired extinguishing effect was achieved using low-density air-mechanical foam from the VVK-5 fire extinguisher and sprayed water with salt additives from a water extinguisher. Based on the obtained research results, we proposed recommendations for the selection of standards for the availability and use of portable fire extinguishers for the effective extinguishing of lithium-ion batteries at the rate of at least 5 kg of charge of working solution or water with salt additives per 5 kWh of energy capacity of a lithium-ion battery. Further research will identify influence patterns of the intensity of extinguishing agent supply on the efficiency of extinguishing lithium-ion batteries. Keywords: lithium-ion battery, fire, irreversible electrothermal process, fire safety.