Lithium battery fire! – which extinguisher?

Lithium batteries on forklift trucks

For fires associated with forklift lithium batteries, the recommended fire extinguisher type is typically a Class D fire extinguisher, specifically designed for metal fires, including lithium. Additionally, some extinguishers with specialised agents, like Lith-X powder or certain clean agent systems, are designed to handle lithium-ion battery fires effectively. It is also crucial to have appropriate fire suppression protocols, as lithium battery fires can reignite due to thermal runaway, so monitoring and cooling post-extinguishing are often necessary.

HOW TO CONTROL A FORKLIFT LITHIUM BATTERY FIRE

If a forklift’s lithium battery catches fire, it is critical to follow specific safety protocols to ensure the safety of people, property, and equipment. Here are the recommended steps:

1. Evacuate the Area Immediately

Move all personnel away from the affected area to avoid exposure to toxic fumes and potential explosions.

2. Alert Emergency Services

Call the fire department or emergency services as lithium fires can be complex and may require professional intervention.

3. Isolate the Battery if Possible

If safe to do so, isolate the battery from the forklift and other equipment to minimise the spread of fire.

4. Use the Appropriate Fire Extinguisher

 

• • Apply a Class D fire extinguisher for lithium metal fires.

• • For fires involving lithium-ion batteries, use fire extinguishers with specialised agents, like Lith-X powder or clean agents, designed for suppressing electrical and battery fires.

5. Cool the Battery

Once the fire is suppressed, continue cooling the battery with water or a suitable cooling agent to prevent re-ignition due to thermal runaway. This can continue for an extended period.

6. Ensure Proper Ventilation

Lithium battery fires produce toxic gases. Ensure the area is ventilated to minimise exposure to hazardous fumes.

7. Monitor the Situation

Continue to monitor the battery after extinguishing the fire to ensure there is no re-ignition. Lithium batteries can reignite even after it seems the fire is out.

8. Report the Incident

Document and report the incident per safety protocols and involve the relevant safety and operational personnel for further investigation.

9. Follow Up with a Safety Inspection

Conduct a thorough inspection of the site and equipment to assess any damage and ensure it is safe to resume operations. Also, review safety protocols and consider additional training or preventative measures to mitigate future risks.

These steps prioritise safety and require cooperation from trained personnel and emergency responders.

10. Evacuate the Area Immediately

Move all personnel away from the affected area to avoid exposure to toxic fumes and potential explosions.

11. Alert Emergency Services

Call 000 (zero, zero, zero) to alert fire department or emergency services as lithium fires can be complex and may require professional intervention.

12.Isolate the Battery is Possible

If safe to do so, isolate the battery from the forklift and other equipment to minimise the spread of fire.

13. Use the Appropriate Fire Extinguisher

 

• • Apply a Class D fire extinguisher for lithium metal fires.

• • For fires involving lithium-ion batteries, use fire extinguishers with specialised agents, like Lith-X powder or clean agents, designed for suppressing electrical and battery fires.

14. Cool the Battery

Once the fire is suppressed, continue cooling the battery with water or a suitable cooling agent to prevent re-ignition due to thermal runaway. This can continue for an extended period.

15. Ensure Proper Ventilation

Lithium battery fires produce toxic gases. Ensure the area is ventilated to minimise exposure to hazardous fumes.

16. Monitor the Situation

Continue to monitor the battery after extinguishing the fire to ensure there is no re-ignition. Lithium batteries can reignite even after it seems the fire is out.

17.Report the Incident

Document and report the incident per safety protocols and involve the relevant safety and operational personnel for further investigation.

18. Follow Up with a Safety Inspection

Conduct a thorough inspection of the site and equipment to assess any damage and ensure it is safe to resume operations. Also, review safety protocols and consider additional training or preventative measures to mitigate future risks.

WHY USE A D CLASS EXTINGUISHER?

The recommended fire extinguishers for handling lithium battery fires are specialized in addressing the unique challenges posed by these fires, which often involve high heat, rapid escalation, and the potential for re-ignition due to thermal runaway. Here is more detail about why they are effective and how they work:

1. Class D Fire Extinguishers

 

• • Composition and Mechanism: Class D fire extinguishers contain a dry powder agent specifically designed to suppress fires involving combustible metals, including lithium. Common agents include sodium chloride (salt) or a specially formulated graphite-based powder.

• • How it Works: These extinguishers create a crust or blanket over the burning material, isolating it from oxygen. The crust smothers the fire, absorbs heat, and prevents the fire from reigniting. For lithium-based fires, the powder suppresses burning metal reactions and helps cool the material.

• • Advantages: Class D agents are specifically designed to stop reactions and contain flames without exacerbating the fire or causing further reactions that water or general-purpose extinguishers might provoke.

2. Specialized Agents for Lithium-Ion Batteries (e.g., Lith-X Powder)

 

• • Lith-X Powder: This agent consists of a finely divided graphite powder designed to absorb heat and isolate burning lithium-ion cells. Lith-X and other agents like copper powder are used for fires involving lithium and similar metal fires.

• • How it Works: The powder covers the burning cells, preventing oxygen from reaching them and reducing their ability to ignite other nearby cells. Unlike water or foam, these powders won’t interact dangerously with burning metals or cause more intense reactions.

• • Effective for Lithium-Ion Batteries: While lithium-ion batteries are less prone to react with moisture than pure lithium metal, they can still reach high temperatures and produce flammable gases when damaged or overheated. Specialized powders prevent the fire from spreading while containing these gases.

3. Limitations of Other Extinguishers

 

• • Water and CO2: Water can be dangerous for fires involving lithium metal, as lithium reacts with water, releasing hydrogen gas and heat, potentially exacerbating the fire. However, water can be used to cool the surrounding area to prevent thermal runaway in lithium-ion battery packs, though it won’t extinguish the fire.

• • Foam and Class B/C Extinguishers: General-purpose extinguishers, including foam or CO2, are typically ineffective against lithium battery fires because they don’t interrupt the intense chemical reactions or thermal runaway of these cells.

4. Heat Absorption and Preventing Thermal Runaway

 

• • Critical for Lithium-Ion Batteries: When a lithium-ion battery is damaged, thermal runaway occurs, where the internal temperature rises rapidly, causing a chain reaction of igniting cells. Effective fire suppression focuses on stopping this runaway effect, cooling the cells to avoid ignition of adjacent materials.

• • Role of Specialized Extinguishers: By cooling the cells and blocking oxygen, Class D extinguishers and specialized powders reduce the risk of re-ignition, control thermal runaway, and prevent damage from spreading.

The Take Away

Fire extinguishers designed for lithium and lithium-ion batteries are built to suppress fires that result from their unique chemical composition and reactions. They work by breaking the fire triangle (heat, fuel, oxygen) through smothering and heat absorption. When handling such fires, training, appropriate extinguishing agents, and caution are critical to ensure effective suppression and safety.

IF LITHIUM BATTERY FIRES DON’T CONSUME OXYGEN; HOW DOES A BLANKET HELP?

While it’s true that the reaction driving a lithium metal fire (particularly in pure lithium) is more of an exothermic chemical reaction than a combustion process dependent solely on oxygen, a few factors help clarify why a blanket approach—like using certain fire suppression powders—can be effective:

1. Thermal Insulation and Heat Absorption

 

• • The primary mechanism for extinguishing lithium fires is controlling heat. Lithium fires generate extremely high temperatures, and using a suppression agent such as a dry powder (e.g., graphite-based or sodium chloride) creates a thermal barrier that helps dissipate heat. This significantly slows down or stops the chemical reaction by reducing the temperature.

• • The blanket effect traps heat inside but also forces it to be absorbed by the powder agent itself, thus cooling the reaction site over time.

2. Isolation from the Environment

 

• • While a pure lithium fire may not depend entirely on atmospheric oxygen, the isolation still prevents external influences like airflow, which can otherwise intensify or spread flames. Additionally, covering the fire with specialized agents prevents the release of flammable vapours or gases that may form during a lithium-ion battery fire.

• • It also reduces the risk of igniting nearby combustible materials, mitigating the spread of fire beyond the battery or metal source.

3. Inhibition of Further Reactions

 

• • In the case of lithium-ion batteries, the reactions involve electrolyte breakdown, cell venting, and sometimes the ignition of flammable gases. By covering the cells with a suppression agent, the blanket prevents the gases from escaping or catching fire. This containment reduces the potential for chain reactions within the battery pack.

• • For lithium metal, the isolation from moisture or other reactive elements in the air can further limit dangerous chemical reactions, since lithium reacts with moisture to release hydrogen gas.

4. Suppression of Combustion and Gas Control in Mixed Fires

 

• • For lithium-ion batteries, which can produce mixed fires involving flammable vapours, plastics, and electrolytes, the “blanket” approach not only controls heat but also cuts off any ongoing combustion that may involve oxygen-dependent materials.

5. Role of the Fire Triangle

 

• • While lithium metal fires may not fit the classical “fire triangle” (heat, fuel, oxygen), most lithium-ion battery fires do involve flammable materials that require oxygen. The “blanketing” agents can isolate and suffocate these reactions as part of a broader containment effort.

THE TAKE AWAY

So, while lithium itself may not need external oxygen to ignite, many of the materials involved in lithium and lithium-ion battery fires do. Creating a thermal barrier helps to cool the reaction site, prevents external influences from worsening the situation, and suppresses secondary combustion processes.

In summary, the effectiveness of a “blanket” or suppression agent is less about cutting off oxygen directly for lithium metal but more about controlling heat, containing reactive byproducts, and preventing the spread of fire through insulation and cooling.

IN SUMMARY

When a lithium battery fire occurs, prioritize safety and use the appropriate fire suppression techniques. Follow these key steps:

When a lithium battery fire occurs, prioritize safety and use the appropriate fire suppression techniques. Follow these key steps:

 

1. 1. Evacuate and Alert: Immediately clear the area and contact emergency services, as lithium battery fires can escalate quickly.

1. 1. Use the Correct Extinguisher: For lithium metal fires, a Class D fire extinguisher is essential, as it provides a dry powder that controls the reaction through heat absorption and isolation. For lithium-ion battery fires, use agents like Lith-X powder or similar specialized suppressants to contain and cool the fire.

1. 1. Utilize a Fire Blanket if Available: Where applicable, use a fire-resistant blanket to smother flames and block heat from spreading. This can help contain the fire and prevent oxygen-dependent combustion from intensifying.

1. 1. Cool the Area: After suppressing visible flames, continue cooling the battery, as lithium battery fires can reignite. Use water spray cautiously around lithium-ion batteries to prevent further thermal runaway.

1. 1. Monitor for Re-ignition: Lithium fires are prone to reignition. Ensure the area is supervised until the risk is entirely neutralized.

1. 1. Post-Incident Review: Document the incident and review safety protocols with all staff. Consider additional training and equipment to enhance readiness for future incidents.
      With the ever increasing use of lithium batteries in the workplace, it is essential that correct guidelines and training are in place to minimise hazards associated with lithium battery fires.

With the ever increasing use of lithium batteries in the workplace, it is essential that correct guidelines and training are in place to minimise hazards associated with lithium battery fires.

Advice

You can obtain more information from the Department of Fire and Emergency Services (DFES) https://www.dfes.wa.gov.au/hazard-information/fire-in-the-home/lithium-ion-batteries or contact fire fighting specialists to ensure you have the best incident response possible in the rare event that a forklift lithium battery catches fire.

As a specialist in forklift safety and training, I am always available to provide guidance, training, and tailored solutions to ensure your team are professionally trained in the safe use of forklift trucks and walkie stackers. For more on how we can help, see our website www.onsiteforkliftlicences.com or call now on 0422 086 968.
Gil Deane.