27/5/2025
A fire broke out at the storage area of a lithium battery factory in Hwaseong, South Korea on July 24 at around 10:30 am local time. The fire, which quickly grew due to explosions caused by more than 35,000 battery cells in the factory, was brought under control after about 5 hours of efforts by 50 fire trucks and about 150 personnel. This tragic fire caused many casualties and injuries. The cause of the fire has not yet been determined.
According to information shared with the public; the factory, operated by a South Korean company established in 2020, was producing primary-type Lithium batteries.
Characteristics of stored batteries
“Primary” batteries, also known as “primary cells”, are disposable batteries. Since the effect of the chemicals that produce electricity in primary batteries cannot be reversed, they cannot be recharged. Batteries that can be recharged and used more than once are called “secondary” batteries.
When we think of lithium batteries; we usually think of mobile phones, laptops and electric vehicles that we use in our daily lives and their rechargeable secondary type batteries. However, in addition to these areas, lithium-based primary type batteries are also produced for use in applications such as sensors, radio communication devices, and medical devices (such as pacemakers). These batteries are generally preferred because of their high energy density and long life. These characteristics may be one of the reasons for the rapid spread of the factory fire. Lithium salts, which are flammable and explosive, are used in the production of lithium batteries. These factors emphasise the importance of lithium battery safety and proper storage practices.
Main causes of battery fires
- Thermal abuse: Ignition of the battery cell by external heat or flame sources.
- Mechanical abuse: Ignition of the battery cell due to damage caused by physical factors such as dropping, crushing and puncturing.
- Electrical abuse: The ignition of the battery during charging due to factors such as charging above its capacity, exposure to high voltage, charging or discharging too fast.
What is thermal runaway phenomenon?
Any of the abusive factors that can occur on batteries can destabilise the structure of the battery, causing it to start generating heat through a chemical reaction. This can lead to “thermal runaway”, which is an uncontrolled reaction. When this reaches a certain level, it triggers chemical reactions that generate more heat and pressure, causing a positive feedback loop. This continues until the battery unit completely burns itself out.
What can be done to prevent fires in lithium battery factory warehouses?
Passive fire safety measures:
To prevent loss of life in case of fire; passive fire safety measures, which are the elements of architectural fire safety, must be fully implemented. These include:
- Planning for the emergency evacuation of personnel; Escape routes and suitability testing of exits
- Correct design and application of emergency lighting and guidance systems to be used during evacuation,
- Determining the fire compartmentation requirements that will stop the spread of fire and/or explosion and confirming that they are correctly implemented. To achieve fire compartmentation, all walls, floors and ceilings of the space must have the fire resistance level specified in the regulation and all openings passing through the space must be isolated with appropriate fire resistant devices and products (e.g. fire doors, dampers, passive insulation applications).
Active fire safety measures:
Selection of extinguishing systems suitable for the storage area:
- This involves the use of appropriate extinguishing systems considering the warehouse ceiling height, storage type and chemical content of the batteries stored. In battery fires, even if complete extinguishing cannot be achieved until the product has consumed itself; suppression can bring the fire under control and prevent it from spreading.
Take measures to monitor and track storage:
- It is essential to monitor the temperature of the batteries; limit the storage charge rate, avoid overcharging and keep the ambient temperature within a safe range.
- Proper ventilation, early detection systems and emergency response plans can also help mitigate the consequences of thermal runaway if it occurs.
- Thermal imaging can be a useful tool to monitor the temperature of battery cells and prevent thermal runaway.
- The storage space must not be used for other purposes and battery units must not be stored externally (mixed storage).
In order to ensure fire safety at this level; it is necessary to have a serious command of current studies and international regulations as well as our national fire regulations. At this stage, we are always with you as Efectis Era Avrasya to ensure fire safety with our engineering services.
For more information, please contact Ridvan Yagmur