CAUSES OF FIRES AND FIRE EXTINGUISHING IN ELECTRIC VEHICLES

Проанализированы известные данные по эксплуатируемым в Российской Федерации типам электротранспорта, а также случаи возгораний на электротранспорте, причины их возникновения. используемые средства пожаротушения. Рассмотрен принцип работы аккумуляторных батарей, применяемых в электротранспортных средствах. Указаны классы пожаров в литий-ионных аккумуляторных батареях. Определены направления разработки огнетушащих веществ и средств их подачи для тушения литий-ионных аккумуляторных батарей.
 The paper analyzes the known data on the available types of electric vehicles operated in the Russian Federation. The cases of fires in electric vehicles in various countries of the world are described. The principle of operation of batteries is considered. There are described the causes of ignition of lithium-ion batteries: mechanical damage of cells; violation of production technology (uneven cutting of electrodes, or ingress of metal particles between the anode and cathode, which leads to damage of the separator); violation of operating rules (improper charging: exceeding the maximum permissible voltage, charging at high currents); germination of lithium chains through the separator; overheating of the battery from external sources. There are specified the classes of fires typical for combustion of lithium-ion batteries. There are given various extinguishing agents used for the most effective and quick decrease of the battery cell temperature as well as their advantages and disadvantages. The laboratory installation and test procedure have been developed to determine the extinguishing capacity of a liquid extinguishing agent when extinguishing lithium-ion batteries. A diagram of a laboratory installation for determining the extinguishing capacity of the extinguishing agent when extinguishing lithium-ion batteries is given. According to this method during the test the temperature readings are constantly monitored. The time from the start of extinguishing to the moment of stopping the flame combustion of the batteries in the model hearth and the time from the moment of stopping the flame combustion to the moment when the temperature inside the model hearth does not exceed 90 °С are recorded. The consumption q of the liquid extinguishing agent is also determined. According to the developed methodology, tests of the liquid extinguishing agent will be carried out. On the basis of FGBU VNIIPO EMERCOME of Russia there are being developed fire extinguishing agents and means of their supply for extinguishing lithium-ion batteries. The directions for the development of fire extinguishing agents and means of their supply for extinguishing lithium-ion batteries have been determined.