Feature Article

Hazards of lithium-ion batteries and equipment

Demand for lithium-ion (Li-ion) batteries is on the rise due to the battery’s high energy density, minimal memory loss, and low loss of charge when not in use. As usage increases from common household items to larger devices and pieces of equipment, the risk of loss also increases. Lithium-ion batteries and the devices or pieces of equipment that utilize them carry a fire risk that may increase if the piece of equipment is improperly used or maintained.

lithium ion battery terminal

One of the primary causes of fire in lithium-ion batteries is due to thermal runaway. A chemical reaction that occurs when more heat is created within the battery than is being dissipated. The heat will degrade the electrolyte inside of the battery causing it to fail. During thermal runaway, the electrolyte degrades into flammable gases, such as hydrogen, hydrocarbons and cardon dioxide. These gases could potentially ignite and cause a fire. Other batteries can become involved quickly in the fire increasing its intensity.

What are some pieces of equipment involved with lithium-ion batteries?

  • Electric vehicles (EV) – Lithium-ion batteries dominate the electric vehicle industry. A few reasons these battery types are favored are due to their high power-to-weight ratio, high energy efficiency, high-temperature performance, and low self-discharge.
  • EV charging stations – There are three levels of vehicle chargers, each having different charging capacities and rates. Level 1 chargers are simple residential units that plug into a 120-volt outlet and can add 3-5 miles of range per charging hour. Level 2 chargers utilize 240-volt power supplies and can provide 10-20 miles per charging hour. Level 3 chargers, also known as “fast chargers” can provide 80% of an EV’s full charge in just 20-30 minutes. These require a 480-volt power supply and are typically only found at rest stops and large gas stations. EV chargers should have built in circuitry protection to prevent current and voltage overload, ground and arc fault, etc. to help protect the vehicle, charger and operator.
  • Solar power system battery bank – The battery bank for solar power systems can utilize lithium-ion batteries. The main function of the battery bank is to store electrical energy for later use. These battery banks can contain multiple batteries connected together in a compact area. A primary driving factor for how many batteries are needed can depend on how much energy is utilized by the property or equipment.

Understanding the hazard & prevention

Electric vehicles (EVs)

  • EV fires can be caused by the following:
  • Failures of the battery management system
  • Manufacturing defect
  • Lack of maintenance
  • Rodents
  • 12v electrical failures

There are 12v batteries in EVs just like the ones in internal combustion engines (ICE) vehicles. A fire starts due to a failure with the 12v battery systems and spreads to other parts of the car. Rodents can also breakdown components of the 12v battery which could lead to a fire. But why are EV battery fires so intense? One major contributor is that that the battery is typically encased in steel, which can make it difficult to get water to the source of the fire (batteries).

What can you do to reduce EV fires?

  • Follow manufacturers specific guidance on maintenance requirements and routinely have vehicle inspected.
  • Only use charging ports and plugs approved or recommended by the manufacturer.
  • If you are in an accident, even a minor one, get the battery and vehicle inspected by a qualified professional.

Note: An electric vehicle does not carry more fire risk than a traditional ICE vehicle. There are more ICE vehicle fires in the world than EV fires per billion miles driven. EV fires get more attention because they involve new technology. This is not to say that EV vehicle fires should be taken lightly as the fire risk is present and if the fire occurs it has different challenges than an ICE vehicle fire.

EV charging stations

Due to the importance of this piece of equipment facilitating the EV charging process, it is critical to maintain and install it properly. If the charging station system fails to do this, then you could have a fire occur on your property or EV.

What can you do to reduce fires involving charging stations?

  • As always, follow the manufacturers’ guidance in maintaining the equipment.
  • Before installation, make sure your homes circuitry can handle the charging load, an electrical study may be needed.
  • The installation should be done by a professional.
  • Only use chargers approved to work with your EV.
  • Lastly, do not use damaged equipment; it should be professionally repaired or replaced.

For charge station installations in parking garages or other enclosed areas, there are additional precautions to consider –

  • Space the chargers far apart.
  • Install monitored smoke detection above all units.
  • Provide automatic sprinklers above the units.
  • Ensure there’s a method to deenergize the system remotely.
  • Review manual to confirm if ventilation is needed during charging.

Solar power battery banks

One of the primary causes of fire in lithium-ion battery banks is due to thermal runaway (as mentioned in the hazard statement above).

What can you do to reduce fires in Solar System lithium-ion Battery Banks? – Think cool, clean, dry and tight.

  • The area for the batteries should be a cool temperature as recommended by the manufacturer.
  • Keep combustibles out of the room or away from batteries.
  • The room should be liquid tight to prevent liquids (e.g., rain) from getting inside and moisture should not build up inside of the room or on batteries.
  • Battery and other electrical connections should be tight and not lose.
  • Non-combustible building material should be used for the construction.
  • Smoke detectors should be installed in the room.
  • Temperature monitoring tied to an alarm system can help alert you to address problems before it leads to a failure of the system or a fire.
  • Have a qualified professional inspect the battery bank and larger solar system as per manufacturers' recommendation.