EV & Heat Management: A Hot Topic

The electric vehicle (EV) market is experiencing exponential growth, driven by rapid technological advancements and increased demand for more sustainable mobility solutions.

Like any evolution it comes with its own set of technical challenges, particularly when it comes to thermal management. Within electric propulsion systems, heat control is critical to the performance and longevity of an electric vehicle and, above all, to user safety.

What role does rubber play in battery protection and EV thermal management? Read on to learn more.

Electric vehicles run on sophisticated propulsion systems, where an electric motor and a battery team up to convert electrical energy into motion. The heat generated by this process can impact the efficiency of the system.

The risk of overheating can’t be overlooked. Overheating can cause other vehicle components like the battery and motor to deteriorate prematurely. 

What’s more, inadequate thermal management can reduce energy efficiency. This affects the vehicle's range and, in extreme cases, poses safety risks. For example, poor heat dissipation can create hot spots in a battery, increasing the risk of thermal failure or fire.

To tackle these thermal challenges, rubber’s unique properties make it an excellent solution.

Rubber has a relatively low thermal conductivity, typically between 0.1 and 0.5 W/m K depending on the type of compound. In contrast, metals such as aluminum and stainless steel have much higher thermal conductivities, around 237 W/m K and 16 W/m K respectively.

This low thermal conductivity allows rubber to transmit heat at a much slower rate compared to other materials, making it an ideal choice as a thermal insulator.

This characteristic allows rubber to protect sensitive components that are exposed to high temperatures, such as lithium-ion batteries and integrated circuits (ICs) in EVs.

Rubber is able to absorb and store a considerable amount of heat before reaching critical temperatures, without deteriorating. For example, the specific heat capacity of natural rubber is about 2 kJ/kg K. That’s much higher than the heat capacity of many metals, meaning rubber can more effectively withstand higher temperatures.

In real-life applications, this heat-resisting property allows rubber to endure repeated thermal cycles (heating-cooling) without losing its essential mechanical properties like elasticity and strength. This behavior is particularly crucial in EV applications, where components are exposed to frequent thermal variations during charging, driving and regenerative braking cycles. At the same time, it minimizes the impacts of thermal fatigue.

The thermal resistance of rubber is also a major plus. For example, elastomers like silicone can withstand temperatures of up to 200°C without degrading, while rubber compounds like NBR (nitrile butadiene) can withstand temperatures between -40°C and +120°C and still retain their mechanical properties.

In addition, rubber offers good chemical resistance. Variants like NBR and EPDM (ethylene propylene diene monomer rubber) are particularly resistant to oils and solvents, which is essential for industrial applications. Vulcanization strengthens the material by creating cross-links that increase its resistance to heat and wear, in turn extending its life.

Rubber is thus an indispensable material and an effective solution for the thermal management of EV.

Durability and reliability

The thermal properties of rubber provide long-lasting protection against temperature fluctuations, helping EV components to last longer. This level of durability is essential to maintain the reliability of electrical systems, particularly under intensive use.

Flexibility and customization

Because rubber is a highly flexible material, it can be molded and customized to meet the specific needs of electric propulsion systems. This flexibility makes it easy to integrate rubber into complex designs, optimizing thermal management where it’s most needed.

Cost reduction

By contributing to the durability and performance of EV components, rubber parts also play a key role in keeping operating and maintenance costs down. By minimizing the risk of overheating and extending system life, rubber helps reduce service requirements and costs associated with breakdowns.c

For OEMs (Original Equipment Manufacturers) that make EVs, the choice of materials is crucial to meet the unique thermal challenges these products present. Partnering with a materials expert like Soucy Baron allows OEMs to develop tailor-made rubber solutions that are perfectly adapted to the specific requirements of electric propulsion systems.

The close partnerships between Soucy Baron and OEMs enable to co-develop innovative solutions that meet complex thermal challenges head-on. This collaborative approach delivers components that are designed to optimize thermal management while also respecting performance and cost constraints.

For more than 50 years, our expertise has stood out thanks to our seasoned technical expertise in materials engineering and our impressive library of more than 900 polymer blend recipes.

With this expertise, custom rubber parts manufacturer Soucy Baron contributes to better thermal performance and greater durability of electric propulsion systems. And that reinforces our position as a trusted partner in the electric mobility sector. To learn more, contact our engineers today.