Causes of Lithium-ion Battery Fires

Lithium-ion battery fires can occur due to various factors, including structural issues, external environments, or battery defects. The main causes of fires in lithium-ion batteries are as follows:

1. Overcharging
   Overcharging increases internal pressure and heats the electrolyte, causing chemical reactions that damage battery cells and may result in fire or explosion.
   Most lithium-ion batteries have a built-in Battery Management System (BMS) to prevent overcharging, but BMS failures can occur.

2. Overdischarging
   Overdischarging means the battery voltage drops too low, destabilizing the cells and potentially causing internal shorts or fire.
   BMS usually prevents this, but faults or cell imbalance can cause issues.

3. Cell Imbalance
   Lithium-ion batteries are made of multiple cells connected in series or parallel. Voltage differences between cells cause imbalance, leading to overheating and fire.

4. Internal Short Circuit
   Short circuits inside battery cells generate heat and may cause fires.
   These can be caused by manufacturing defects, damage, or excessive charge/discharge.

5. Physical Damage
   Physical impacts or pressure can damage battery cells, leading to short circuits, overheating, or fire.
   Damaged casings may leak electrolyte or cause electrical shorts.

6. Overheating
   High temperatures during use or charging can damage cells and increase fire risk.
   If temperature exceeds limits, chemical reactions may ignite fires.

7. Poor Quality Batteries
   Manufacturing defects or poor quality control can leave faulty cells or circuits, increasing fire risk.
   Non-certified or low-quality batteries typically have lower safety standards.

8. Use of Incompatible Chargers
   Using low-quality or incompatible chargers may cause overvoltage, overcharging, or overheating, leading to fires.

9. BMS Failure
   BMS controls charging, discharging, temperature, and voltage. Failures can disable protection and cause fires.

10. Exceeding Battery Lifespan
    Old batteries degrade, increasing risk of overheating or damage during charging, which can cause fires.

Fire Prevention Measures

1. Use certified batteries and chargers.

2. Regularly inspect battery status and BMS function.

3. Avoid overcharging and overdischarging; maintain recommended charge levels.

4. Ensure battery protection systems are working.

5. Avoid high-temperature environments.

6. Confirm proper connection during charging.

7. Store and handle batteries safely to prevent damage.

Following these guidelines helps extend battery life and prevent fires.