Most Popular Thermally Conductive Adhesives for Battery Packs

Most Popular Thermally Conductive Adhesives for Battery Packs

January 13, 2025

Battery pack adhesive solutions that incorporate thermally conductive adhesives provide thermal management systems with the ability to safely dissipate excessive heat from main battery parts under high load. Since batteries in electric vehicles (EVs) store and deliver significant amounts of energy, they are prone to generate heat. This causes the liquid catalyst electrolyte inside the battery to start to evaporate, damaging the battery’s internal structure and causing the lead plates inside it to corrode, shortening the battery life.

Therefore, there is huge pressure on the manufacturers and designers of EV batteries to select the right thermally conductive adhesive. These adhesives are particularly suited to providing a secure mechanical connection between parts and minimizing thermal resistance, making them crucial for high-performance battery applications.

Top Thermally Conductive Adhesives for Battery Packs

Product Name Company Type of Adhesive Thermal conductivity Temperature Range Curing Time Key Features Applications
TC 2035 DOWSIL Silicone based 3.3 W/mK -45°C to 200°C 10 minutes at 150°C or 30 minutes at 125°C High thermal conductivity, Reduced thermal resistivity, Stability under high temperature Battery Packs, Boards and Assemblies
TC-2030 Dow Corning Silicone based 2.7 W/mK -45 to 200°C Room-temperature curing within 24 hrs, 1-2 hours at 100°C High thermal conductivity, Maintains structural integrity, High Reliability EV Battery packs, electronic enclosures
EA 9497 Henkel Loctite Epoxy based 1.4 W/mK Upto 200°C Room-temperature curing within 24 hrs High temperature resistance, high compression strength, strong adhesion under thermal stress Electronic assemblies and battery packs
SE 4486 Dow Corning Silicone based 1.59 W/mK -45 to 200ºC Room-temperature curing full capacity in 4-7 hrs Good dielectric strength, Non-corrosive Bonding in consumer electronics
8329TCM MG Chemicals Epoxy based 1.4 W/mK -40°C to 150°C 24 hours room temperature or 1 hour at 65 °C Strong electrical insulation,
High mechanical strength,
Strong resistance to humidity
Attach heat sinks
PyroDuct 597-A Aremco Ceramic based 9.1 W/mK Upto  927°C Room-temperature curing within 1-2 hrs High temperature resistance, Electrical conductivity, Corrosion resistance Battery packs in high-temperature environments, industrial electronics
THERM-A-GAP Gel 30 Parker Chomerics Silicone based 3.5 W/mK Upto 200°C Doesn’t need curing Easily dispensable,
Low thermal impedance,
High bulk thermal conductivity
Battery pack gaps, thermal interface for irregular surfaces
TCOR Electrolube Silicone based 1.8 W/mK -50 to 230°C 24 hours at  20°C High bond strength,
Wide temperature range, High thermal conductivity
EV batteries, electronic modules, applications requiring RTV flexibility
PRIMA-SOLDER (EG8050) AI Technology Silver filled epoxy 7.9 W/mK 80 to 100 °C 120 hours  at  25 °C or 2 hours at 125°C High melting point, Excellent Wetting Properties, Non-corrosive Circuit boards, Battery pack assemblies
UR5097 Electrolube Polyurethane based 0.65 W/mK -40°C to 110°C Room-temperature curing within 24 hrs High thermal conductivity, Flame retardancy, Moisture and Chemical Resistance EV battery modules, Electrical circuits.

Each of these adhesives offers unique properties suited for different applications. Still, the overall goal remains the same, which is to facilitate the movement of heat from the battery pack while providing adequate protection to the battery pack.

Types of Thermally Conductive Adhesives

Understanding the different types of thermally conductive adhesives is essential to choosing the right one for battery pack applications. Here’s a closer look at three primary types: epoxy, silicone, and polyurethane.

Epoxy Adhesives:

Epoxy adhesives are most commonly used in battery pack applications due to their good mechanical strength and compatibility in adhering to the cellular structures of metal and ceramics . Therefore, epoxy adhesives can be used for bonding battery systems involving metals, ceramics, and composite materials.

Various types of Epoxy

Figure 1: Various types of Epoxy (Loctite® AA H4500 (right) and PRIMA-SOLDER™ (left)).

Features of epoxy adhesives:

  • Thermal conductivity: Epoxy adhesives have good heat transfer properties that help to dissipate heat effectively.
  • Chemical Resistance: They can handle chemicals, moisture, and tough environments, making them an ideal option in rough conditions.
  • Strong Bonds: Epoxy adhesives create a firm bond, which is important for tasks where mechanical integrity is key.

Due to the above-mentioned benefits, epoxy is an excellent choice for various applications. However, they can be more brittle than the other two types, which limits their use in situations needing flexibility.

Silicone Adhesives:

Silicone-based adhesives are highly valued for their flexibility and excellent thermal stability, especially in high-temperature situations. They are selected for applications where vibration resistance and temperature fluctuations are a concern.

Features of Silicone Adhesives:

  • Flexibility: Silicone adhesives retain their elasticity across a wide temperature range, making them ideal for dynamic applications where components may expand and contract.
  • High-Temperature Resistance: Silicones can endure temperatures up to 200°C, which makes them perfect for high-heat environments like EV batteries.
  • Good Electrical Insulation: Besides thermal conductivity, silicone adhesives also offer outstanding electrical insulation.

While silicone adhesives may not provide the same bonding strength as epoxies, their durability in extreme conditions makes them a preferred option for battery pack applications.

Polyurethane Adhesives:

Polyurethane adhesives are less commonly used for battery pack applications but are considered where flexibility and impact resistance are concerned. They have the ability to stretch due to polymer and fill the minute gap without causing the interface to fail.

Features of Polyurethane Adhesives:

  • Elasticity: Polyurethane glues stay flexible and can handle vibrations and impacts, making them great for setups that experience mechanical stress.
  • Lower Curing Temperatures: These glues harden at lower temperatures, which is helpful in setups with heat-sensitive parts.
  • Strong Bonding: They stick well to many surfaces, including plastics and metals, making them useful in various battery pack designs.

However, polyurethane glues usually have lower thermal conductivity than epoxies and silicones, which limits their use in systems that require high levels of heat transfer.

Conclusion

Thermally conductive adhesives play a crucial role in the design and production of efficient battery packs and other advanced battery systems. With the increasing need for energy storage solutions, managing heat effectively has become vital for prolonging battery life, maintaining efficiency, and ensuring the safety of these systems.

Thermally conductive adhesives

Figure 2: Thermally conductive adhesives are important for designing efficient battery pack systems.

Choosing the right adhesive requires considering several factors: thermal conductivity, mechanical strength, flexibility, and resistance to environmental conditions. Epoxy, silicone, and polyurethane adhesives each have their benefits, and the best choice depends on the specific requirements of the battery system. As adhesive technology continues to advance, manufacturers will have more options to enhance thermal management.

Enhance your battery’s thermal performance with Thermtest solutions. Reach out to our experts today for tailored guidance and solutions!

 

Frequently Asked Questions

What adhesives are used in EV batteries?

Thermally conductive adhesives like epoxy, silicone, and polyurethane are used in EV batteries since they provide not only strong bonding but also efficient heat dissipation.

What is the best thermally conductive adhesive?

The best thermally conductive adhesive depends upon its application. For high strength, epoxies like Henkel Loctite EA 9497 are most commonly used. On the other hand, if high flexibility and temperature stability are required silicone adhesives like Dow Corning TC-2030 are ideal.

 

References

8329TCM. (2024, September). Retrieved from DigiKey.com

AI Technology PRIMA-SOLDER EG8050-E Epoxy Paste Adhesive 3 cc EFD Syringe. (n.d.). Retrieved from https://www.ellsworth.com

Dow Corning TC-2030. (2013). Retrieved from Ellsworth Adhesives: https://www.ellsworth.com

Dow Corning®SE 4489 Thermally Conductive Adhesives. (2010, September). Retrieved from Octopart.com

DOWSIL™ TC-2035 CV Adhesive. (2021). Retrieved from Dow.com: https://www.dow.com

Electrically and Thermally Conductive Adhesives and Coatings. (n.d.). Retrieved from https://www.aremco.com

LOCTITE® EA 9497. (2014, October). Retrieved from Henkel adhesives: https://www.henkel-adhesives.com/tz/en/product/structural-adhesives/loctite_ea_9497.html

RTV Thermally Conductive Oxime. (n.d.). Retrieved from https://electrolube.com/

THERM-A-GAP GEL 30 High Performance Fully Cured Dispensable GELS. (n.d.). Retrieved from https://ph.parker.com

Thermally Conductive Polyurethane Potting Compound. (n.d.). Retrieved from https://electrolube.com

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