The Role of Flexo in Battery Safety
- Published: March 24, 2026
By Rodger Mort, Chief Operating Officer at Packaging and Crating Technologies (PACT®)
We certainly live in an electronic age! From electric vehicles and e-bikes to cell phones and tablets, new e-mobility equipment and handheld devices are continually entering our modern society to make our lives more efficient. Regardless of their size and function, they all have one thing in common: they are powered by lithium-ion batteries, which do offer positive rechargeable benefits, but simultaneously present dangerous hazards. Every day around the world, there is death and destruction because a lithium battery was not charged, stored or recycled properly.
In fact, according to the U.S. Consumer Product Safety Commission, while the total nationwide data for 2025 has not yet been finalized, reports indicate a continuing upward trend from 2024, with over 1.3 million negative incidents linked to lithium battery fires. Leaving any lithium battery to charge unattended is a major safety hazard, but can become a crime scene especially in large, populated cities like New York, Los Angeles and Chicago where entire blocks have burned down and many human lives have been lost, often firefighters, police officers, EMS technicians and other first responders.
Not only do lithium-ion battery blazes generate intense heat as they burn for hours, sometimes days, but they can also eject shrapnel, smoke and hydrogen fluoride gas, a toxic threat to people and the atmosphere. That’s why our global manufacturing company that serves the commercial, industrial and military sectors created a solution to help mitigate explosive fires and emission of noxious gases caused by lithium batteries.
In 2019, we developed a patented, fire-suppressant packaging wrap designed to control thermal runaway, a phenomenon in which a lithium-ion cell enters a volatile and uncontrollable, self-heating state caused by extremely high temperatures, banging or puncturing during transit, or internal defect, which can easily combust.
Thermo ShieldTMcontrols lithium battery fires by creating a non-toxic vapor cloud that immediately cools the internal environment of the package. Image courtesy of PACT
Producing Fire-Resistant Paper
The paper is manufactured using 50lb virgin Kraft bag stock, which is printed on a flexographic preprint press. Two coats of our proprietary ink are applied to one side of the paper. The resulting roll-stock is then shipped to our plant. Special liners are applied to the top and bottom of the material with sprayed glue every 6 inches. This three-layer reel of 250 lineal feet has now been converted into a powerful, lightweight weapon against lithium battery fires.
Specifically, when the paper reaches a temperature of 200°F, it undergoes a chemical reaction that absorbs the heat and releases moisture. Simply stated, the paper creates a non-toxic vapor cloud that immediately cools the internal environment of the package, while limiting oxygen around the payload.
This process allows the individual battery cell to burn out on its own, prevent thermal runaway from spreading to other areas of the container, suppress a potentially deadly fire explosion, and shield the surrounding environment from a flammable mixture of lethal gases. It can contain temperatures up to 1,800°F, while restricting the temperature outside of the wrap to 140°F, which prevents both the fire and residual spoke from being released.
Taking the Technology Further
Taking this technology one step further, we designed a special solution just for e-mobility equipment, such as electric vehicles, electric buses, electric scooters, electric bikes, battery packs and renewable energy storage systems, which effectively stops thermal runaway propagation between lithium-battery cells. Here, the same 50lb virgin Kraft bag stock is applied four total coats of proprietary ink: two coats on one side of the paper and two coats on the opposite side. After the printing process, the roll-stock is slit into the proper width. Should thermal runaway occur, the rogue cell will burn out quickly, preventing all other cells from also entering into a thermal runaway state, while retaining 100% of the battery charge.
For smaller handheld devices like cell phones, pagers, Bluetooth headsets, laptops, tablets and smartwatches, a smaller fire-retardant bag comprised of the same material can be utilized to safely transport and recycle these items, a huge benefit to the airline industry where such devices have combusted during flight.
TR SleeveTM serves as a heat and flame barrier in e-mobility equipment, in which a thin layer of Thermo ShieldTM is wrapped around each battery cell to mitigate thermal runaway. Image courtesy of PACT
A Real-World Application
As a powerful example of the technology in action, one of our clients is an e-scrap removal company that reduces the amount of unwanted electronic equipment in landfills. A key facet of electronics recycling is handling batteries, whose dangerous chemicals necessitate special care. Further, the company is required to dispose of damaged, defective or recalled batteries.
Originally using vermiculite, a sand-based insulator to recycle these dangerous items, the company executives discovered that our product would allow them to safely pack and fit more batteries in a single shipment, thus reducing shipping costs. More importantly, our fire-suppressant packaging wrap mitigated dangerous thermal runaway events, even for batteries charged at high levels. Since incorporating our solution into its battery recycling process, the company has experienced significantly improved efficiency and zero runaway events, resulting in a smoother operation and peace of mind within its employees.
In conclusion, as the number of electronic equipment and devices continues to increase in society, so does the threat of deadly lithium-ion battery blazes, which power them. As an industry, we must remain committed to creating innovative solutions that save both human lives and the environment.
About the Author
Rodger Mort is Chief Operating Officer at Packaging and Crating Technologies (PACT), a global manufacturer of sustainable, corrugated cardboard packaging containers for the commercial, industrial, and military sectors. He brings over 40 years of green packaging experience to the industry with a specialty of designing paper-based packaging material that suppresses and controls lithium-ion battery fires by mitigating thermal runaway, a phenomenon in which a lithium-ion cell enters a volatile and uncontrollable, self-heating state that can cause lethal explosions. Visit www.pactww.com or www.pactthermoshield.com for more information.
