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    HomeOpinionInterviewsChallenges and Developments in Thermal Management of Electrified Powertrains

    Challenges and Developments in Thermal Management of Electrified Powertrains

    With the escalation of innovations, products are turning to take a nano form from the gigantic. With the reduced space and heat dissipation, thermal management has become an uphill climb. The thermodynamic-based technology has its applications in varied industries aviation, electronics, medical, material processing, and HVAC systems. Technological innovation has made it mandatory in almost every growing industry. The global thermal management market is estimated to be USD 12.8 billion by 2025 (forecast year) from USD 8.8 billion in 2020 (estimated year), at a CAGR of 8.2% between 2020 to 2025.

    Thermal management is also an imperial part of the evolving EV industry. The growing industry is presently in a phase where challenges and opportunities came along on the floor. EV fire raging incident had witnessed a little shake for the industry. To resolve the snag, thermal management systems can be possible stability to this unprecedented stir. Researchers predicted that the temperature homogeneity needed between the battery pack for a long-range and comfortable thermal experience can only be achieved by the right thermal interface material. Electric mobility demands new solutions and innovative systems in thermal management to provide passenger comfort without impacting vehicle range and protect battery lifetime and performance by securing ideal operating conditions even during the fast charging operations.

    It is the right set of circumstances for thermal management companies to jump into the EV revolution with some innovations in thermal materials.

    ELE Times Subeditor and correspondent Sheeba Chauhan had an exclusive conversation with Padmanabha Shakthivelu, General Manager, Electrolube India to expound on this topic further. Excerpt:

    TimesEV: Electrolube’s roots since 1941 are doing wonders in the market. What challenges are coming your way while operating in the Indian market?

    Padmanabha Shakthivelu: Requirements from India vary from time to time. A few years ago, it was UPS systems then the LED industry, and now EV. Every time industry throws new challenges and varied requirements. We were able to meet customer requirements by quickly adapting to the needs with technical know-how, global R&D support, and domestic manufacturing.

    TimesEV: How is heat dissipated directly proportional to the surface area? What product range do you have for managing this type of dissipation?

    Padmanabha Shakthivelu: Heat is lost from a component to its surroundings at the surface of the component. The rate of loss of heat will increase with the surface area of the component; a small device producing 10 watts will reach a higher temperature than a similar powered device with a larger surface area.

    This is where heat sinks are used – varying in size and shape, heat sinks can be designed to offer a significantly increased surface area to maximize heat dissipation. They are typically connected to components that generate a large amount of thermal energy when used and therefore dissipate such energy away from the device to avoid failure due to over-heating.

    In order to ensure full contact between the two metal surfaces between the component and the heat sink; Thermal Management products are used. Metal surfaces, even when polished to a fine degree, have a certain amount of roughness. It can therefore be deduced that when two metal surfaces are placed together contact is not 100% and there will always be an air gap between the two surfaces. The use of a Thermal Management product between such gaps ensures complete contact between the two surfaces and in turn more efficient heat dissipation.

    TimesEV: What are the most widely used thermal interface materials (TIMs)?

    Padmanabha Shakthivelu: The most widely used TIMs is the traditional thermal paste, available in silicone and non-silicone, which are applied at thicknesses <100µm. However, Electrolube also has solutions for other applications where the interface is greater than 100µm such as our 2-part silicone gap filler, GF400 (see Q8). The choice of Thermal Management product will be dependent on the customer’s application and product requirements. EL’s Thermal Management product range can take many forms including thermal pastes, putties, gap fillers, a room temperature vulcanized (RTV) silicone, to name a few.

    TimesEV: What challenges are emerging in thermal management with the increased use of nanotechnology in modern electronics?

    Padmanabha Shakthivelu: With the increased use of nanotechnology and product miniaturization, the need for efficient thermal management within devices is also increasing. As devices get smaller, the spacing between components also gets smaller and any heat generated by these components is concentrated at specific areas of the PCB. Components that generate a lot of heat could therefore adversely affect other nearby components which, due to miniaturization, are much closer to one another. Increased heat generation in turn can have a detrimental effect on the product lifespan. By using effective thermal management techniques, excessive heat can be dissipated, enabling densely populated designs to be achieved without compromising the life expectancy of the device.

    TimesEV: “Newton’s Law of cooling” being prominent in Thermal Management, would you like to elaborate it further to our readers?

    Padmanabha Shakthivelu: Newton’s law of cooling states that the rate of loss of heat is proportional to the temperature difference between the body and its surroundings. If we consider a heat producing electronic component in isolation then, during operation, its’ temperature will rise until the heat produced within the device becomes equal to the heat lost to the surroundings and the device has reached equilibrium. As the temperature of the component rises the heat loss increases.

    When the heat loss per second equates to the heat produced per second within the component, the device will have achieved its equilibrium temperature. This temperature may be high enough to significantly shorten the life of the component or even cause the device to fail. Thermal Management products provide a solution to this issue and overall prevent the entire device from overheating thus increasing the reliability of the device. A similar approach can be applied to a complete circuit or device which incorporates heat producing individual components.

    TimesEV: What are your recent product launches in the thermal management segment? Padmanabha Shakthivelu: GF400 is a two-part, liquid silicone-based gap filler, which can either be cured at room temperature or accelerated with heat. Following cure, GF400 forms a low modulus elastomer that prevents the ‘pump-out phenomenon’, ensuring minimal degradation of effective heat dissipation. It is soft and compliant, making it ideal for low stress applications, and provides a wide operating temperature range between -50 to +200°C. GF400 is also low viscosity, enabling easier dispensing, and provides high thermal conductivity of 4.0 W/m.K The GF400 has a straightforward mix ratio of 1:1 and a fast cure time of 20 minutes at 100°C, vastly speeding up throughput. GF400 is also UL94 V-O approved and has excellent dielectric strength of 9 kV/mm.

    GF400 is extremely adaptable and can be used in a multitude of applications from printed circuit board assembly and housing electronic components discretely to automotive electronics, including HEV and NEV batteries, power electronics, LEDs, and fiber optic telecoms equipment.

    TimesEV: Being at a position of responsibility, it surely comes with a bombardment of, how would you like to define those challenges?

    Padmanabha Shakthivelu: As head of the Technical Support Team, I am responsible for delivering technical support and guidance for our customers including advice on product selection and/or application technique. Challenges come from a wide variety of applications across a broad range of industries including automotive, aerospace and many more. It is our goal to ensure that our customers achieve a streamlined production process and efficient heat transfer both in initial application and final use. Here at Electrolube, we thrive on challenges, so if you have a particular thermal management issue, please contact our Technical Support team.

    TimesEV: What are the expansion plans of Electrolube for the year 2022?

    Padmanabha Shakthivelu: Global expansion plans for our Thermal, Coatings, and Resin products focusing on Automotive, specifically EV applications.

    Sheeba Chauhan | Sub Editor |TimesEV