In today’s world, lithium-ion batteries power an array of electronic devices, making them an integral part of our daily lives. Whether it’s your smartphone, laptop, or tablet, these devices often accompany us during travel. However, when it comes to transporting lithium battery-powered gadgets, there are specific rules and precautions you need to be aware of, especially when you’re flying. The Federal Aviation Administration (FAA) has set clear guidelines on how to handle these batteries during air travel.
Transporting Lithium Batteries on Flights
According to the FAA, devices equipped with lithium metal or lithium-ion batteries, such as laptops, smartphones, and tablets, should ideally be carried in your carry-on baggage. This precaution is due to the potential risks associated with lithium battery devices in checked luggage. In checked bags, these devices must be entirely powered off and protected to prevent accidental activation or damage. Devices that contain heating elements capable of generating extreme heat, like curling irons, must have these elements isolated to prevent the risk of a fire hazard. Moreover, spare (uninstalled) lithium metal and lithium-ion batteries are strictly prohibited in checked baggage and must always be carried in your carry-on. But why these stringent rules?
The FAA conducted tests that revealed when large electronic devices like laptops overheat in checked luggage, the presence of aerosol canisters like hairspray or dry shampoo increases the risk of combustion. In such cases, the potential for explosion becomes a danger to the entire aircraft. While the risks are more significant when dealing with a lithium battery fire on an airplane, it’s essential to understand why lithium batteries catch fire and what to do if it happens during your daily routine.
Understanding Thermal Runaway: The Firestarter
In a previous blog, we discussed how to prevent lithium batteries from catching fire, but now let’s delve into why these batteries ignite. Lithium-ion and lithium-metal cells can undergo a process called thermal runaway during failure conditions. Thermal runaway leads to a sudden increase in battery cell temperature and pressure, along with the release of flammable gas. This released gas is often ignited by the battery’s high temperature, resulting in a fire. One primary reason for thermal runaway is microscopic metal particles coming into contact with different parts of the battery, leading to a short-circuit.
Typically, a minor short circuit causes an increased self-discharge, generating minimal heat due to the low discharging energy. However, when enough microscopic metal particles accumulate at a specific spot, a significant electrical short can develop, resulting in substantial current flow between the positive and negative plates, ultimately causing combustion.
Warning Signs of an Impending Battery Fire
In most cases, there are clear indicators that a battery is about to catch fire. It will become excessively hot, swell up, and may even develop a lump or bulge, altering the device’s appearance. You might notice discoloration, damage, blistering, and smoke. In such a situation, avoid touching a swelling or ruptured device with your bare hands.
Action Plan When Your Battery Catches Fire
If your lithium-ion battery catches fire, it contains a small amount of lithium metal and can be doused with water. However, lithium-metal batteries require a Class D fire extinguisher. Water reacts with lithium, and if a Class D extinguisher isn’t available, you can pour water to prevent the fire from spreading.
To extinguish a lithium-ion fire effectively, use a foam extinguisher, CO2, ABC dry chemical, powdered graphite, copper powder, or soda (sodium carbonate), just like you would put out other combustible fires. Reserve Class D extinguishers for lithium-metal fires only.
If you cannot extinguish a burning lithium-ion battery fire, let the pack burn out in a controlled and safe manner. Be aware that each cell may burn on its timetable when hot. Afterward, place the seemingly burned-out pack outside for a while.
In case other combustible materials catch fire as a result of the lithium battery fire, use the appropriate extinguishing agent to douse these secondary fires. It’s crucial to address each type of fire with the right extinguishing agent.
Remember, only trained and qualified personnel should attempt to fight a lithium-metal or lithium-ion battery fire.
Class D Fire Extinguishers: The Specialized Solution
Class D fire extinguishers, also known as dry powder extinguishers, work by separating the fuel from the oxygen element or by removing the heat element of the fire triangle. However, it’s essential to note that dry powder extinguishers are designed for Class D or combustible metal fires exclusively.
Understanding the science behind lithium battery fires, recognizing warning signs, and knowing how to react in case of a fire is essential to ensure your safety and the safety of those around you. These measures are particularly vital in the context of air travel, where strict rules and guidelines must be followed to prevent potential disasters.
