The safety of energy storage systems has always been a topic of concern to everyone. In the event of an accident, in addition to the hazards caused by fire and explosion itself, toxic chemicals may also be released to cause chemical hazards, and even relevant personnel may be repairing or rescuing the storage system. When the power system is not connected, electrical hazards or physical hazards may also occur.

Energy storage fire cause

There are many reasons for the fire of the energy storage system, ranging from climatic factors to improper operation of personnel, errors in the integration process, and failure of the battery management system. The most commonly discussed are battery aging and thermal runaway. Thermal runaway is a problem. It refers to the excessive release of electrical energy that causes the temperature to rise, thereby forming a short-circuit current. The reasons are usually divided into four categories: first, the battery itself is overcharged and discharged; second, the external environment is too high; third, due to material penetration, extrusion and mechanical deformation caused by bending; finally, internal short circuit (ISC).

When a fire occurs, it will be classified into four categories A, B, C, and D due to different fire causes and extinguishing methods. Category A fires are ordinary fires that can be directly extinguished or cooled with water; Category B fires are oil or gas fires , Oxygen needs to be isolated by masking method; Class C fires are electrical fires, usually electrical equipment that is energized, the power must be cut off first, and non-conductive agents should be used to prevent the fire from spreading; Class D fires are metal fires, where the metal refers to It is a reactive metal and requires a special type of fire extinguisher to effectively control it. Generally speaking, energy storage fires are often classified as Class C fires, but in fact, they include both the combustion of the battery shell and battery electrodes (Class A) and the combustion of flammable liquid electrolytes (Class B). Therefore, it is a composite type of fire. type of fire, and we can also assess the potential risk of fire through the fuel, oxidant, and heat from the ignition source.

Energy storage fire extinguishing

When thermal runaway occurs in the energy storage system, flammable gas will be generated. If it accumulates to a certain level and comes into contact with the air, there is a certain probability that a chemical reaction will occur, resulting in faster combustion or even explosion. Especially when the thermal runaway reaction of lithium-ion batteries occurs, it is easy to The phenomenon of re-ignition occurs, and the water source cannot effectively extinguish the fire. It is only used as a cooling effect. The fire can only be extinguished when the chemical reaction is completely completed. When the energy system catches fire, there may still be residual electricity. Although the system has been powered off, it is necessary to avoid electric shock during rescue.

In order to reduce the occurrence of energy storage accidents, in addition to formulating perfect safety regulations, it is also necessary to train relevant personnel in real-time judgment and protection knowledge. The most important thing is to expect the technology of energy storage to become more and more mature. In recent years, accidents have occurred. The frequency and frequency have dropped significantly. In addition to the continuous improvement of battery technology, various energy storage manufacturers have successively introduced relevant safety and fire protection measures with different patented technologies, hoping to improve the safety factor of the energy storage system. It is also recommended to select equipment with international safety labels when the system is capable, and give priority to system safety.