Thermal management for the automotive industry

Miniaturization and system integration are at the forefront of automotive electronics development, which in turn is driven by the demand for vehicles with higher fuel efficiency, improved safety, seamless connectivity and autonomous functionality. As a result, circuit design has evolved to meet the demand for higher energy efficiency.

With smaller electronic components and higher energy density, thermal management in vehicles becomes an issue.

With the smaller devices having less surface area to act as heat sinks, dissipating heat from these systems remains an operational and safety challenge.

Thermal management is an evolving branch of vehicle design that uses advanced thermal interface materials (TIMs) to allow better heat dissipation from the circuitry.

Heat management in the vehicle interior

Some of the main heat-generating electronic components in the vehicle interior are:

Vehicle infotainment systems

These highly integrated, powerful systems with multiple displays, through which the driver controls a variety of functions such as Bluetooth, GPS, audio, etc.

The challenge: Today's infotainment systems contain a large number of circuits and LED chips that generate a lot of heat, which requires proper thermal management.

Advanced driver assistance systems (ADAS)
ADAS integrates multiple systems throughout the vehicle, such as B. Sensors, cameras, connectivity functions and above all a data module that combines the information received from the different components.

The challenge: The high data output of these systems requires effective heat dissipation that ensures continuous reliability and function.

Thermal management outside the vehicle cabin

Outside the cabin, thermal management becomes a bit more complex as components are not only exposed to higher operating temperatures, but also to various environmental factors such as humidity, salts, corrosive fumes and extreme weather conditions.

They are often sealed for mechanical and physical protection, making it even more difficult to dissipate excess heat and cooling.

These components include:

Engine Control Units (ECUs)
ECUs control all electronic aspects of a vehicle, from the powertrain to the central locking system. ECUs rely on an uninterrupted flow of data between input sensors and output components to control engine function.

The Challenge: Due to the large amount of information generated by these systems, thermal management is critical to ensure functional integrity and continuity.

Brake system control
These and other sensor classes are additional systems that are located outside the passenger cabin and generate heat.

The Challenge: Fast and efficient heat dissipation from these systems is critical to the smooth and safe operation of any vehicle.

E-mobility with even greater challenges for thermal management

The rise of companies like Tesla has forced automakers to redefine corporate strategies and adapt to market demands driven by new consumer preferences. Increasing demand for electric vehicles (EVs) and hybrid electric vehicles (HEVs) presents automakers with new design challenges to reduce manufacturing costs, increase battery range, reduce weight, and improve safety and reliability.

Like internal combustion engines, powertrains are at the heart of electric vehicles. The main components in electric vehicles are

• the battery pack,
• the electric motor and
• the energy conversion system.

One of the biggest challenges in electric vehicle design is maximizing power output while minimizing battery size and weight.

One strategy is to combine the power conversion system and electric motor into a single unit while reducing the size of each component. While this approach improves the power density and efficiency of the e-drive, it increases the risk of motor failure due to overheating. Therefore, thermal management is critical in both components.

electric motors

Electric motors convert electrical energy into mechanical energy and are one of the main components of EV powertrains.

Challenge: Heat can reduce a motor's performance and shorten its lifespan. Therefore, it is important to conduct heat away from the engine quickly and efficiently.

energy conversion systems

The vehicle's power electronics are the part of the powertrain that controls the electrical energy and transmits it to the other systems, as well as controlling the speed and torque of the engine. It consists of three main electronic components:

• the on-board charger (OBC),
• the inverter system (IGBT modules) and
• the DC/DC converter.

To save space and reduce overall weight, thereby increasing range, the design strategy focused on downsizing and component consolidation.

The challenge: These components work with high voltages and consume a lot of energy, which helps to reduce the charging time. However, the heat generated is difficult to control because the reduced size of the components offers less surface area for heat dissipation.

battery systems

The design of these systems has a major impact on the range, power density, charging time and long-term performance of an electric vehicle.

A challenge: As with all electronic components, thermal management becomes more difficult as battery packs get smaller. In addition to thermal management, the structural integrity of the cell-to-cell and cell-to-pack connections must also be guaranteed.

Solutions for thermal management in the automotive sector

To solve these diverse design challenges and also to provide options for our OEM partners, we have developed a wide range of advanced thermal materials including gap pads, thermal compounds, thermally conductive adhesives (TCAs) and thermal encapsulants.

Our thermal compounds and gap fillers displace air at the component/heatsink interface to aid in heat dissipation. Our gap fillers, which have one of the highest thermal conductivities in the industry, are a promising choice for efficiently conducting battery cell heat out of the battery modules and then out of the battery packs themselves.

Thermally conductive adhesives perform a similar function but provide additional structural integrity by creating a permanent bond at the interface of mating surfaces. They are commonly used in infotainment, autonomous and ADAS systems in vehicles. In electric vehicles, they are commonly used for cell-to-cell and cell-to-pack connections to ensure structural integrity and pack cooling.

Finally, our thermally conductive potting compounds help protect components from overheating while providing excellent protection from shock, impact and other environmental influences. They have proven extremely effective in thermal management of ECU sensors and LED lights.

In electric vehicles, our encapsulants are reliable thermal management materials that help manufacturers build smaller yet more reliable electric motors with higher power densities.