FAQ (Q&A)

• The processing method. LithiumPrevent 200R is suitable for injection molding, while LithiumPrevent 200REX is designed for extrusion.

• LithiumPrevent 200REX achieves UL 94 V-0 rating at 2 mm thickness and demonstrates excellent resistance to ignition. UL2596 Torch & Grit performance: withstands 2 cycles at 2 mm, 4 cycles at 3 mm, and 5 cycles at 4 mm.

Refer to SDS. Avoid contamination or contact with acetal resins (POM) to prevent hazardous reactions.

LithiumPrevent is a passive, intumescent thermoplastic used to help contain thermal runaway and reduce propagation risk, while also supporting electrical insulation and arcing mitigation as part of the overall pack design, that can be injection molded or extruded into battery pack components.

LithiumPrevent 200REX is the extrusion formulation in the LithiumPrevent family, intended for continuous profiles/sheets.

LithiumPrevent 200REX is positioned for cell containment, busbar isolation, and pack-lid defense in OEM battery systems.

• LithiumPrevent starts reacting and expanding at 200°C with an expansion rate of 2–3x original volume.

• The price will depend on some variants, such as quantity, project complexity, timeline, etc. But Pyrophobic’s LithiumPrevent 200REX is an extrudable intumescent thermoplastic that enables continuous profiles/sheets and feature integration, reducing part count and assembly complexity.
• Additionally, LithiumPrevent 200REX provides intumescent fire protection plus electrical insulation (e.g., UL 94 V-0 at 2 mm; CTI 561; PLC-0 in HAI/HWI), combining multiple safety functions in a single material, which can replace multi-layer stacks (e.g., passive insulators alone).
• We will be glad to set up a quick call for a better understanding of the project and elaborate a specific quote.

• It will depend on some variants, such as quantity, project complexity, address, etc.
• LithiumPrevent 200REX can be supplied as pellets, powder or finished parts.
• We will be glad to set up a quick call for a better understanding of the project and elaborate a specific quote with lead time.

• Approximately 200 degrees Celsius (which is consistent with the trigger temperature for thermal runaway).

Thickness depends on many factors: battery chemistry, cell or module energy capacity, overall test strategy. That said, generally the minimum thickness we recommend is 2mm of material until additional information is provided. For extruded applications, 2mm is the thinnest the material can be made.

• LithiumPrevent 200REX can be used in cell containment, busbar isolation, and pack-lid defense, and integrated into module housings, spacers, and enclosures as extruded continuous profiles/sheets.
• The LithiumPrevent family targets thermal runaway containment/propagation prevention for EV and ESS/BESS.

LithiumPrevent 200REX lists: UL 94 V-0 at 2 mm, CTI 561 (ASTM D3638), HAI PLC-0 (UL 746A), and Hot Wire Ignition PLC-0 (ASTM D3874).

If it stays in a more confined space, it creates a more dense char, otherwise it expands and will take the path of least resistance.

It means the material was tested to UL 94 vertical burn and achieved a V-0 classification at a 2 mm thickness (the thickness matters and should be cited correctly in compliance documentation).

• The expansion ratio for the base LithiumPrevent material is 20x, however we have formulas that are available in both 10x and 15x as well. The lower the expansion ratio, the more rigid and less expensive the material is. However at 10x the fire performance is significantly reduced.

CTI (Comparative Tracking Index) is used to compare a material’s resistance to electrical tracking under wet/contaminated conditions; it’s commonly referenced when engineers are managing creepage/clearance and tracking risk in dirty environments. (LithiumPrevent 200REX lists CTI 561).

Pyrophobic lists HAI per UL 746A and HWI per ASTM D3874 for LithiumPrevent 200REX. HAI evaluates how many arcs are needed to ignite a plastic; HWI evaluates ignition resistance near hot wire sources. Both are commonly used to characterize ignition behavior of polymeric insulators.

Pyrophobic specifically calls out use cases like cell containment, busbar isolation, and pack lid defense, consistent with where engineered profiles can add both thermal and electrical functions.

The material must be designed into the system in such a way that this is addressed. The material is rigid enough that in most applications, battery expansion will not cause a significant gap. Materials that are pliable, like foams and caulks cannot protect against runaway and will fail by the time it has begun to occur.

Intumescent systems absorb heat and expand to form a protective char layer, creating a thermal and physical barrier that prevents flame from spreading and can seal gaps (key in thermal runaway scenarios).

You can screw into the material, particularly the more rigid versions that expand less but it is preferable to use a fire rated adhesive or simply mount using pressure or clip features.

• Extrusion is a continuous process: molten polymer is pushed through a die to create constant cross-section profiles (e.g., channels, trims, sheets), typically with lower tooling cost and quicker tooling lead.
• Injection molding is cyclic: molten polymer is injected into a closed mold to make complex 3D parts, enabling detailed features. Injection molding is performed under higher pressures.
• These differences guide whether you choose LithiumPrevent 200R (injection-moldable) or LithiumPrevent 200REX (extrudable).

• Mica is a proven, passive high-temperature electrical/thermal insulator (widely used under lids, as barriers, etc.), but is often brittle, labor-intensive to process into intricate shapes, and may raise sourcing/ethical-mining concerns.
• LithiumPrevent 200REX, by contrast, is an intumescent thermoplastic that can be extruded into tailored continuous profiles and expands 2–3x, providing an active char-forming barrier plus electrical insulation (e.g., CTI 561; UL 94 V-0 at 2 mm). This enables design integration (fewer parts/assembly steps) and functional layering that mica alone doesn’t provide.

• LithiumPrevent 200REX expansion (reaction) starts at 200 °C.

• LithiumPrevent 200REX expands 2 to 3 times their size.

• Forms: Pellets and powder (for extrusion).
• Process: Extrusion for LithiumPrevent 200REX.
• The LithiumPrevent family also supports injection molding via LithiumPrevent 200 and LithiumPrevent 200R.
• Pyrophobic can prototyping via CNC’d blocks and production via injection molding, thermoforming, or extrusion depending on design/economics.

• The LithiumPrevent family is developed for thermal runaway containment/propagation prevention, certified by UL 9540A and other fire tests (e.g., UL 94).
• LithiumPrevent 200REX itself lists UL 94 V-0 (2 mm) and electrical ignition/tracking performance.

• Yes, LithiumPrevent 200REX is listed as UL 94 V-0 (2 mm).

• Technical literature explains that intumescent materials generate an expanding, insulating char under heat, whereas passive insulators (e.g., mica, aerogel) primarily resist heat transfer and can require layering/sealing to achieve similar protection.
• LithiumPrevent 200REX provides better passive fire safety solutions because of their active expansion and multi-functionality (thermal + electrical + arc suppression) of its intumescent thermoplastics.

• The LithiumPrevent 200REX TDS lists Americas, Europe and Asia-Pacific but you can contact Pyrophobic for other regions too.

• Pyrophobic’s own product structure is:
• LithiumPrevent 200 / 200R: injection molding formulations.
• LithiumPrevent 200REX: extrusion formulation.
• So the decision is typically driven by whether you need complex 3D features (injection molding) or continuous profiles/sheets (extrusion).

• Pyrophobic explicitly references working toward required standards “including UL 9540A,” and lists UL 9540A among relevant “Fire Test Standards” on its LithiumPrevent page. UL 9540A is the widely used test method for evaluating thermal runaway fire propagation in battery energy storage systems.

• Pyrophobic states LithiumPrevent is “proven effective through internal testing, independent testing, and evaluations at NASA, the FAA, and DNV,” and includes quotes on the LithiumPrevent page describing those evaluations.

• Yes, but needs to be analyzed case by case.
• It can be positioned as a different tool: intumescents add active expansion + char formation (gap sealing/char barrier behavior), whereas mica/aerogels are typically passive thermal barriers.

• Pyrophobic states they prototype by producing blocks and CNC machining, and notes that with wall thicknesses ≥ 1 mm they have been able to make complex shapes.

• Choose LithiumPrevent 200 or LithiumPrevent 200R (injection-moldable) for complex 3D parts that need integrated features (bosses, clips, fastener seats).
• Choose LithiumPrevent 200REX (extrudable) for linear profiles/sheets (cell spacers, channel sections, lid perimeters) with lower-cost/faster dies and continuous production.

• UL describes “Torch and Grit” (UL 2596) as a test method used to evaluate ignition resistance/behavior under a torch-and-grit exposure scenario.

• Yes, LithiumPrevent LP200REX is listed as UL 94 V-0 at 2 mm, CTI 561 (ASTM D3638) and HAI/HWI PLC-0, the exact metrics pack teams request for flammability, tracking, and ignition resistance.

• Yes, especially when you need an active barrier in an engineered profile. LithiumPrevent 200REX is an extrudable, intumescent thermoplastic that expands 2–3x and carries UL 94 V-0 (2 mm) and CTI 561.
• LithiumPrevent 200REX provides gap-sealing and electrical insulation in continuous custom profiles that will reduce parts/operations and add active protection.

• Yes, but we recommend a minimum thickness of 2 mm for great performance.

• Yes, the LithiumPrevent family has been used by companies in the EVs and ESS with outstanding results to prevent and contain thermal runaways in lithium-ion batteries.

• Yes, LithiumPrevent 200REX published as UL 94 V-0 (2 mm), CTI 561 and HAI/HWI PLC-0, with expansion rate of 2–3x, and the intended functions such as char barrier, arc suppression and smoke path interruption.
• LithiumPrevent have been helping a variety of companies to contain propagation when properly integrated.

• Those are excellent passive barriers. LithiumPrevent 200REX doesn’t compete on sub-millimeter films, it complements them by delivering active expansion in engineered plastic geometries (perimeters, channels, busbar isolators) with published UL/CTI/ignition metrics.
• Many packs use both: films/papers in tight gaps and LP200REX profiles where expansion and sealing add value.

• Mica is a solid choice for planar, high-temperature electrical insulation but when you want the barrier to do more than passively endure heat, we recommend LithiumPrevent 200REX.
• LithiumPrevent 200REX is an intumescent thermoplastic designed for extrusion into continuous, custom profiles or sheets, that under heat it starts expanding around 200°C and grows 2–3x, forming an insulating char that can seal gaps, block flame paths, and interrupt arcing/tracking.
• In summary, keep mica where you need flat and passive high-temp boards. And use LithiumPrevent 200REX where active expansion and engineered cross-sections (perimeter seals, channels, spacers and busbar isolators) will help contain thermal propagation and reduce part count/assembly steps.

• PyroThin is excellent when your constraint is ultrathin and low-mass passive thermal blocking.
• But LithiumPrevent 200REX does something more: it’s an intumescent thermoplastic for extrusion that expands 2–3x, creating an active, char-forming barrier that can help seal gaps, block flame paths, and interrupt arcing/tracking.
• Additionally it comes with published electrical safety metrics (e.g., UL 94 V-0 at 2 mm, CTI 561, HAI/HWI PLC-0) that pack engineers often need to cite.
• Because it’s extrudable, you can design continuous, custom profiles or sheets to add purposeful geometry and reduce part count/assembly steps.
• In summary, keep PyroThin where you’re thickness and weight limited, and use LithiumPrevent 200REX where active expansion in an engineered cross-section plus electrical credentials deliver more value to the system.

• Inherently Fire resistant, a higher degree of fire protection than adding a fire retardant to an engineered plastic.
• Highly insulating char which provides a thermal barrier is formed through an endothermic reaction.
• Electrically insulative (high Dielectric Breakdown strength).
• When dealing with lithium battery fire (i.e. class delta fire), this material stays up with rapid rise in temperature by reacting instantaneously.

• Fire resistant, a higher degree of fire protection than fire retardant.
• Highly insulating char which provides a thermal barrier is formed through an endothermic reaction.
• Electrically insulative (high Dielectric Breakdown strength).
• When dealing with lithium battery fire (i.e. class delta fire), this material stays up with rapid rise in temperature by reacting instantaneously.

• LithiumPrevent 200: Semi-Rigid for Injection Molding.
• LithiumPrevent 200R: Rigid for Injection Molding.
• LithiumPrevent 200REX: For Extrusion.
• All formulations feature the same proprietary intumescent technology, delivering trusted protection against lithium-ion battery hazards:
• Contains thermal runaway at the cell or module level.
• Provides thermal separation between cells and modules.
• Controls explosive pressure events.
• Prevents cascading fire propagation.
• Blocks heat transfer to adjacent combustibles.

• For prototyping, we make blocks to size and CNC machine the material. So long as wall thicknesses are 1mm+ we have not had any issues making parts into very complex shapes.
• For production, we can do it via injection mold, thermoform or extrude depending on the needs of the design and what is more economical.

• Injection molding, thermoforming and extrusion are all capable of utilizing existing tooling with little parameter changes in most cases but review on a case by case basis is required.
• Proprietary knowledge of speeds and feeds require trials and experimentation but we have the ability to train and support as needed.

• The product page lists Start Expansion Temperature: 200°C.

• The product page lists Expansion Rate: 2–3x original volume.

• The product page lists UL 94 Section 8 – Vertical Burn: 2 mm, V-0.

CTI is a tracking-resistance metric in the presence of aqueous contaminants; the LP 200REX page lists CTI 561 (ASTM D3638).

HAI (High-Current Arc Ignition) measures how many arcs are needed to ignite a plastic; LithiumPrevent 200REX lists UL 746A Sect 33 – HAI PLC-0.

LithiumPrevent 200REX lists ASTM D3874 – Hot Wire Ignition PLC-0; ASTM describes D3874 as assessing ignition resistance near hot-wire sources.

• LithiumPrevent 200REX is presented as the extrusion formulation.
• Pyrophobic also lists LithiumPrevent 200 / 200R for injection molding.

The LithiumPrevent 200REX page publishes a performance table including tensile strength/modulus/elongation, Izod impact, HDT, and CLTE.

• Pyrophobic explicitly calls out busbar isolation and pack-lid defense; those are common “perimeter/profile” applications for extruded parts.

Pyrophobic describes LithiumPrevent as helping prevent thermal runaway propagation and improve battery system safety; it’s not typically described as preventing a cell from entering runaway in the first place.

Pyrophobic calls LithiumPrevent a passive fire containment solution, while the material itself is intumescent (reacts under heat).

• Pyrophobic lists standards on its Tests & Certifications page, including UL 9540A (propagating thermal runaway) and UL 94.

• Yes. Pyrophobic provides a downloadable LithiumPrevent 200REX TDS.
• Link LithiumPrevent 200REX (LP200REX) TDS: https://pyrophobic.com/wp-content/uploads/2025/10/TDS_LP200REX_2025-09-16_Website-3.pdf

Pyrophobic positions 200 and 200R for injection molding and 200REX for extrusion (different processing routes for different part geometries).

A safe, accurate way to answer is: it’s often a different role (extruded, intumescent, multi-functional barriers) and may be used alongside passive films/boards depending on design constraints and requirements.

• Pyrophobic provides a LithiumPrevent data sheet page and a PDF datasheet.
• LithiumPrevent 200 data sheet (product TDS – Technical Data Sheet) link: https://pyrophobic.com/wp-content/uploads/2025/08/LP200-TDS-Aug-5-2025.pdf
• LithiumPrevent 200R data sheet (product TDS – Technical Data Sheet) link: https://pyrophobic.com/wp-content/uploads/2025/08/LP200R-TDS-Aug-5-2025.pdf
• LithiumPrevent 200REX data sheet (product TDS – Technical Data Sheet) link: https://pyrophobic.com/wp-content/uploads/2025/10/TDS_LP200REX_2025-09-16_Website-3.pdf