Breaking news! Burning for nearly 10 hours! A container truck full of lithium batteries caught fire!

According to the latest report from Taiwan media, at noon on January 6 (Monday), a "solar energy storage cabinet" container truck carrying 3,200 lithium batteries overturned near the exit of Huwei Interchange on National Highway 1. After 16 hours of alert, it suddenly caught fire. This is the first lithium battery energy storage cabinet fire in Taiwan.

It is understood that a solar energy company in Hsinchu recently commissioned a freight company to transport a storage cabinet containing 3,200 lithium batteries to an energy storage company in Douliu City, Yunlin for installation. However, at noon on the 6th, when the container truck carrying the energy storage cabinet turned out of the Huwei Interchange, it unfortunately overturned on Yunlin 145 B Line Road.

After receiving the alarm, the fire department quickly dispatched rescue vehicles to the scene. After arriving, firefighters found that smoke was constantly coming out of the chassis of the container truck, and the temperature at the scene was measured at 51 degrees using a fire robot. After learning that the container was loaded with more than 3,200 lithium iron phosphate batteries, the firefighters were worried that spraying water for rescue would aggravate the thermal reaction of the battery and cause an explosion. Since there was no similar rescue precedent, the firefighters decided to take a cautious approach.

According to the battery manufacturer, the power of this batch of lithium iron phosphate batteries was about 50%. Professionals suggested that if the internal battery was damaged and the gas pressure in the cabinet was unknown, the energy storage cabinet should be left to stand and wait for the reaction to end to prevent an explosion. Therefore, the firefighters kept a guard on the scene all night. However, at about 5 a.m. on the 7th, the energy storage cabinet suddenly started smoking and caught fire, the cabinet temperature quickly rose to 60 degrees, and the fire gradually spread.

The energy storage cabinet continued to burn for nearly 10 hours before it burned out at around 2 p.m. on the 7th, but it suddenly reignited not long after, and the core temperature was still 100 degrees two hours later. After the temperature dropped significantly, the fire department found a crane to tow the container truck away and temporarily placed it on the bank of the Xinhuwei River, where there are fewer people, waiting for the manufacturer to pick it up.

Causes of lithium battery fires

Battery fires occur as a result of the interaction between oxidants, combustibles and ignition sources, a process that can be summarized as the "thermal runaway triangle". As long as any element of this triangle is destroyed, the combustion process can be terminated. Understanding the "thermal runaway triangle" is crucial to effectively responding to battery fires.

Under conditions of thermal abuse, electrical abuse or mechanical abuse, the interior of a lithium-ion battery may heat up abnormally, triggering a series of exothermic reactions, causing the battery temperature and reaction rate to rise sharply, and ultimately causing thermal runaway. During the thermal runaway process, there are many types of combustibles in the battery, including graphite negative electrodes, electrolyte solvents, combustible gases and metals, and the composition of these combustibles is constantly changing. To make matters more complicated, battery thermal runaway not only relies on external oxygen, but the high-temperature decomposition of the positive electrode material can also release oxygen. The characteristics of battery thermal runaway fire are also quite distinct:

1. The temperature rise rate is extremely high, reaching more than 100℃/s, and the surface temperature exceeds 1,000 degrees, which can easily cause large-scale fires;

2. Accompanied by violent jet fire, the heat release rate is large, and the flame is as high as 1~2 meters;

3. The spread speed is fast, and the thermal runaway of a single battery in the module can easily spread to the entire group;

4. It is difficult to extinguish the fire because the heat mainly comes from the inside of the battery, the outer shell hinders the action of the fire extinguishing agent, and it is easy to reignite;

5. There is an explosion risk. The gases generated by thermal runaway include CO, CO2, CH4, C2H4, H2 and electrolyte vapor;

The thermal runaway gas is toxic, and gases such as CO can reduce the oxygen supply capacity of hemoglobin, causing serious personal injury.

Post-fire handling is very important

1. Evacuation and safety of personnel

Immediate evacuation of personnel: Ensure that all personnel on site (including staff, surrounding personnel, etc.) evacuate to a safe area as soon as possible and stay away from the fire scene.

Maintain a safe distance: When a fire occurs, ensure that personnel maintain a sufficient safe distance, especially at least 100 meters away from the burning lithium battery pack and high-voltage power supply.

Wear protective equipment: Emergency personnel should wear appropriate protective equipment, including fire-resistant clothing, respirators, etc.

2. Cut off the power supply

Turn off the power supply of the battery pack: Cut off the connection between the battery pack and the grid as much as possible to prevent the battery from continuing to discharge during the fire. Emergency personnel should use a power-off device (such as an electrical isolation switch) to cut off the connection between the battery and the external grid.

Turn off the inverter and battery management system (BMS): Ensure that the inverter and battery management system (BMS) are turned off to prevent the battery from continuing to output power during the fire.

3. Extinguish the source of fire

Choice of fire extinguisher: Since lithium battery fires are a special type of electrical fire, the use of ordinary fire extinguishers (such as water or foam fire extinguishers) will aggravate the fire. Use dry powder fire extinguishers or carbon dioxide fire extinguishers, which do not react chemically with lithium batteries.

Do not use water to extinguish fires: Water is very dangerous to lithium battery fires and may cause chemical reactions within the battery to intensify or even cause an explosion. Avoid any water source coming into contact with the fire area.

Monitoring during fire extinguishing: When using a dry powder fire extinguisher, pay attention to the scope of the fire extinguishing to ensure that the fire source is completely covered to prevent the fire from re-igniting.

4. Cooling and preventing thermal runaway

Cooling the battery pack: Once the fire is extinguished, the battery pack should be cooled as soon as possible to prevent thermal runaway, where the battery continues to heat itself and cause a secondary fire. The battery temperature can be lowered by spraying water, air circulation, or special cooling equipment.

Monitoring temperature changes: Use temperature sensors and infrared devices to monitor the temperature of the battery pack in real time to prevent the fire from re-igniting.

5. Fire monitoring and isolation

Isolate the fire source: If the fire source is only in part of the battery pack or module, immediately isolate it from the unburned part to prevent the fire from spreading to other battery modules.

Continuous monitoring: After the fire is extinguished, the fire scene and surrounding areas are continuously monitored to ensure that there is no re-ignition and that there is no leakage of harmful gases.

6. Environmental protection and harmful gas treatment

Ventilation and gas treatment: When a lithium battery fire occurs, harmful gases (such as hydrogen fluoride gas, carbon dioxide, etc.) may be released. Good ventilation should be maintained on site to avoid the accumulation of toxic gases. Use a dedicated exhaust system or gas absorption equipment to treat these harmful gases.

Environmental testing: Use professional equipment to detect harmful substances in the air to ensure the safety of the fire area and its surrounding environment.

7. Post-fire assessment and disposal

Loss assessment: After the fire is extinguished, a loss assessment should be conducted as soon as possible to check the degree of damage to equipment such as lithium battery packs, battery management systems, and inverters.

Cleaning up the fire scene: Clean up fire residues and harmful waste, especially battery cells or battery packs that have been damaged by the fire. Damaged lithium batteries need to be disposed of in accordance with the requirements for hazardous waste treatment.

8. Accident investigation and cause analysis

Investigate the cause of the fire: Organize professionals to investigate the cause of the fire, including battery failure, system failure, external factors, etc. Find out the specific cause through investigation and propose improvement measures.

Accident records and data collection: Record fire scene data, monitoring data, and equipment operation logs as a basis for accident analysis and improvement.

9. Improve safety precautions

Safety assessment: Based on the results of the fire investigation, evaluate whether the existing energy storage system safety measures are effective. It may be necessary to strengthen the deployment of fire-fighting equipment, train emergency response personnel, optimize the battery management system, etc.

Improve safety standards: Based on the lessons learned from the incident, review the design and safety standards of the energy storage power station, and make necessary upgrades and improvements to prevent similar incidents from happening again.

10. Emergency response and training

Regular drills: Regularly conduct fire emergency drills for energy storage power station staff to ensure that all personnel are familiar with the emergency response process.

Improve emergency response capabilities: Strengthen coordination and cooperation with local fire departments, improve emergency response capabilities, and ensure that fires can be handled quickly in the event of a fire.

Energy storage safety is no small matter! Energy storage battery fires not only threaten facility safety, but also pose serious challenges to the environment and personnel health. Understanding its causes, mastering fire characteristics, and choosing appropriate fire extinguishing agents and strategies are the keys to preventing and responding to fires.