While it’s true that LiFePO4 batteries are safer, it’s not accurate to say they’re completely immune to fire. Like any energy storage system, under extreme conditions, they can still catch fire. Here are a few scenarios where this could happen:
Physical Damage: If a LiFePO4 battery is punctured or severely damaged, the internal components could be compromised. While the battery is less likely to burst into flames compared to other lithium-ion types, physical damage can still cause a short circuit, which may lead to overheating and potentially fire.
Extreme Overcharging: Modern LiFePO4 batteries come equipped with Battery Management Systems (BMS) to prevent overcharging, but if this system fails, overcharging can occur. If the voltage is pushed too far beyond safe limits, the battery can overheat and possibly ignite.
Manufacturing Defects: While rare, poor manufacturing quality can lead to internal defects. In these cases, microscopic particles or poorly aligned components could create weak spots that become prone to short circuits, which could result in fires in extreme cases.
Exposure to External Heat: LiFePO4 batteries are generally more heat-tolerant than other lithium chemistries, but if exposed to extremely high temperatures (like in a house fire or a car engine), they could ignite. The threshold is much higher than with other batteries, but it’s not impossible.
Further reading : LiFePO4 Thermal Runaway Prevention and Safety