Automotive – Lighting & Electronic venting

EV Battery Vents

PTFE Material and Track-Etched Membrane Technologies Designed Specifically for EV Batteries

PTFE Material and Track-Etched Membrane Technologies Designed Specifically for EV Batteries

As the demand for EVs continues to rise, ensuring their safety and reliability is paramount. At Porex, we provide cutting-edge battery vents to renowned companies worldwide, built on two proven venting technologies: track-etched membrane and sintered PTFE. Our vents enable proper pressure equalization and rapid gas release in case of failure, while effectively preventing dust and moisture infiltration into the battery.

With our expertise in material science, Porex offers customizable porous polymer solutions for various automotive venting needs, including sintered PTFE and track-etched membrane technologies. Our engineers can tailor a solution specific to your device, leveraging a range of materials, chemical compositions, geometries, assembly techniques, and additives. Experience the benefits of POREX Virtek™ PTFE and Unique-Mem® track-etched membrane EV battery vents for enhanced pressure equalization and ventilation.

Electric Vehicle Battery Burst Vent

Protect your EV battery packs with high-performance Porex Virtek PTFE dual-stage safety vents without needing burst pins. Our fully assembled vents give you a fast-release solution for thermal runaway and off-gassing that allows for both passive air venting and burst action in one component.

Robust structure does not damage easily like expanded PTFE material
No change in airflow when handled
IP rated for extreme thermal cycling
Easy, flexible assembly – attach via ultrasonic, heat welding, overmolding, or a variety of other techniques
Fully assembled
Can be designed to act as a breather and safety vent
100% PFOA free – Compliant with (EC) 1907/2006 REACH / Regulation (EU) 2019/1021 POP

Porex Virtek® PTFE – Automotive / Oleophobic product range (hydrophobic & oleophobic)

Item Number	IP Rating †	WEP^* mbar (Typical)	Typical Airflow l/hr/cm² @70mbar	Filtration Efficiency** >99.99%	Thickness mm	Max Operating Temp °C	Salt Fog^$
PMA10^‡	64,67	370	75	0.4 µ	0.18	260	No pen.
PMA15^‡	65,67,68	520	25	0.1 µ	0.25	260	No pen.
PMA20^‡	65,66,67,68	1050	7	0.1 µ	0.19	260	No pen

† IEC std. 60529; IP 68 is a user defined and results must be verified by the user
^*WEP = Water Entry Pressure
^**According to IEST RP-CC007.2 2009
^$ASTM B117-11 test method
^***Laminated polyolefin mesh backing
^‡ Oleophobic, AATCC TM 118 – Grade 8
Moisture Vapor Transmission Rate approx. 900g/m2/day. ASTM E96-16 water escaped from sealed cup @ 23±2°C, 50±10%rH chamber.
Properties are typical and not meant for specifications. Selected options and adhesives may affect properties
RoHS, WEEE, REACH Compliant (PFOA Free)

Options for Customizing Sintered PTFE EV Battery Vents

Physical properties

When incorporating a sintered PTFE membrane into your product, it’s critical to understand the physical properties impacting the materials and functionality of the part including:

Understanding typical material properties will guide you in selecting the right polymer for your device’s function and operating conditions. The above characteristics can be highlighted or downplayed based on your specific product needs. Below is a chart that shows the common materials with their physical properties; however, this is not an exhaustive list.

Air flow rate: the volume of air being delivered at a given pressure drop through a specific area. This is a critical measure for designing a venting membrane. One important thing to note – air flow rate will increase through the same vent as the pressure drop increases.
Water entry pressure (WEP): the amount of water pressure required to have water break through the membrane. This is a critical measure when designing a water-resistant venting or filtering membrane.
Operating temperature: the temperature range at which the part will be required to operate. For Porex Virtek PTFE membrane, this value is 260°C / 500°F continuous.
Other key characteristics: Porex Virtek PTFE membrane is an extremely versatile material that is used in numerous markets and applications. Other application-specific characteristics that may be required for your application can include filtration efficiency, moisture vapor transmission rate, Gurley number, % reflectivity, and dielectric properties.

Chemical properties

Porex Virtek PTFE waterproof membrane is one of the most chemically resistant materials available in the market. There are only a handful of fluorinated acids that are not chemically compatible with sintered PTFE membranes, so it is always your safest choice if unknown chemicals may be in contact with the component.

Chemicals	PTFE
Acids (non oxidizing)	Good
Bases	Good
Oil	Good
Aromatic Solvents	Good
Non-Polar Alphatic Solvent	Good
Polar-Aprotic Solvents	Good
Polar-Protic Solvents	Good
Halogenated Solvent	Good
Oxidizing Agents	Good

Material options

Polytetrafluoroethylene (PTFE)
For applications in need of ultra-hydrophobicity, high-temperature tolerances, high chemical resistance, and excellent robustness, sintered and skived PTFE membrane technology is a perfect choice.

Using our wide range of customizable solutions, we work closely with your engineering team to define your specifications and select the best PTFE membrane for your application.

Additive options

Below are some common additives and treatments that expand the potential functionality of your PTFE membrane:

Oleophobic treatment
Polypropylene scrim support layer
Adhesive backing
Screen Printing

Geometric options

Porex Virtek PTFE membrane material begins as a 330 mm wide format (between 0.1 and 3.0 mm thick) and can be cut into porous PTFE sheets and other format options such as:

Slit rolls (8 – 330 mm)
Die-cut discs and various shapes
Rotary-cut plugs and discs
Cut discs “in web”
Water jet cut shapes
Zoned adhesive disc and other shapes
Rods & molded or spiral tubes
Thermoformed shapes
Porous PTFE sheets

Our engineers can work with you to better understand your manufacturing process and determine which size, shape, and dimensions are the best fit for your application.

Assembly & converting options

Customizable assembly and converting options for sintered PTFE are endless. Some of the more common methodologies include:

Thermal & ultrasonic welding
Overmolding
Die-cutting
Press fit
Pressure-sensitive adhesive (PSA)

To potentially decrease your assembly time and complexity, our engineers can work with you to better understand how your final product or device will be made. In many cases, we can combine multiple parts into one that is custom engineered.

If you require secondary processing of sheet and film products to meet your product design challenges, Porex also offers a Preferred Converter Program that can serve smaller order quantities.

Unique-Mem® for Optimal Venting & Degassing of EV Batteries

Our innovative Unique-Mem® track-etched membranes offer reliable outgassing and protection from the ingress of liquid, dust, dirt, and other contaminants. In the event of abnormal operations, this novel membrane technology will burst at a predefined overpressure rate to ensure spontaneous high-volume gas release from the battery compartment. This game-changing solution not only protects the battery modules but can, more importantly, ensure the safety of electric vehicle users.

Key Benefits

High precision breathing and/or bursting for emergency degassing & pressure compensation in the event of thermal runaways
Battery housing protection against intrusion of liquids, dust and dirt (IP67 class)
Membrane can be bonded directly to the insert via ultrasonic welding, laser welding or insert-molding
100% Free of PFOA: Compliant with (EC) 1907/2006 REACH / Regulation (EU) 2019/1021 POP

Punch & US-welding
Laser-welding

PET Track-Etched Membranes unlaminated
PET Track-Etched Membranes laminated with PET/ PP non-woven material
Additional membrane materials available upon request

Highlighted Case Study

EV Battery Safety Vents

A manufacturer of electric vehicle (EV) lithium batteries reached out to us to develop and design a hydrophobic membrane that would meet their specifications as it relates to temperature stability, air flow, water entry pressure, and constant and reliable expansion properties.

Read Full Case Study

Porex Virtek® IP-Rated Protection Vents Brochure

Explore the portfolio of robust Porex Virtek® IP-Rated Protection Vents for electronics and automotive applications.

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Oxyphen EV Battery Safety Vents Application Brochure

Learn more about Oxyphen’s hydrophobic all-in-one solution that protects critical internal components from the ingress of liquid, dust, dirt, and other contaminants while also having the ability to burst at predefined overpressures to prevent potential explosions from taking place in the event of thermal runaway.

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IP-Rated Vents for Automotive Applications Brochure

Discover the capabilities of POREX® IP-rated PTFE vents specifically designed for automotive applications, enabling rapid pressure equalization and ensuring effective protection.

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