Thermal management is an often overlooked yet imperative part of our modern lives. Device miniaturization whilst increasing performance, battery packs charging and discharging safely at a rate consumers demand, and a data-hungry world putting pressure on power requirements all show the need for advanced thermal management solutions.
From August 30-31, the Thermal Management Expo and Conference took place in Cleveland, Ohio, for the first time. This event, co-located with Ceramics Expo, was timely for both end users and material providers, with speakers ranging from Meta to W.L. Gore.
IDTechEx was on the scientific advisory board for this event and provides some of the most comprehensive market research on thermal management, including Thermal Interface Materials, Thermal Management for Electric Vehicles, Thermal Management for 5G, and Thermal Management for ADAS.
In this article, IDTechEx highlights some of the key discussion points and takeaways from this 2-day event.
Thermal Management in Different Electric Vehicle Segments
The panel, led by IDTechEx, discussed thermal management challenges and novel concepts in the battery packs in cars (10s of kWh), trucks (100s of kWh), and small vehicles (<1kWh). The automotive market is the largest volume demand and the most cost-driven, providing solutions that can improve battery performance in extreme ambient conditions and high charge/discharge rates is critical for future development.
The automotive market is trending toward batteries with greater vehicle integration, such as cell-to-pack and cell-to-body designs. Multi-functional materials are a key enabling technology to enable this while also providing the performance and safety required. For example, the panelist from Rogers Corporation outlined their ProCell material for use between battery cells that can provide compression for cell expansion whilst also providing thermal runaway propagation protection.
As highlighted by Romeo Power, commercial vehicles can utilize batteries with over 700kWh in some cases. The sheer amount of capacity leads to challenges in keeping the temperature difference across the pack in a close window and a focus on safety.
Beam Global discussed its approach to passive thermal management of smaller battery packs (2-wheelers, drones, etc.) using a phase change material (PCM), where active cooling systems may not be viable. PCMs present challenges in application due to the limit of energy absorption achievable and the mechanical properties. However, Beam Global, after its acquisition of AllCell Technologies uses its Phase Change Composite to enable thermal management in smaller vehicle segments whilst also providing protection from thermal runaway propagation.
Many vehicle segments are electrifying, and each poses its own challenges and opportunities. For this reason, IDTechEx's research has detailed many EV segments, with an example being its research on Electric Vehicles: Land, Sea, and Air.
Current and Future Trends for Thermal Interface Materials
When considering thermal management materials, the use of thermal interface materials (TIMs) is a key consideration. A key panel at the event included representatives from materials suppliers, including Laird, Parker, and Henkel. They discussed the current and future trends in TIM formulation and application. At a high level, it was agreed that greases and PCMs are useful for more extreme scenarios and that gap filler pads and liquids would be the most commonly used. When a TIM is also required to give structure, that is where adhesives and tapes come in.
The big application that every TIM supplier wants to get involved in is the EV battery market, thanks to the large volumes required. The panel discussed the needs for this market in terms of TIM fillers. TIM formulation is a balancing act; a greater loading of fillers increases thermal conductivity but also increases weight, abrasiveness, and cost. To date, alumina is by far the most commonly used filler in this application due to its low cost. Boron nitride (BN) is much less common but certainly has potential in higher-performance systems. Considering 5L of TIM could be used in an EV battery, with 70% wt loading, that leads to fillers being required on the scale of 10s of kg per vehicle, a huge opportunity for both TIM manufacturers and filler suppliers.
What's Changing in the Thermal Management of Consumer Electronics
Whilst smartphones and several other consumer electronics devices may feel like mature markets, their thermal management is still evolving. This was highlighted by the keynote speaker from Meta. Meta outlined the challenges with device densification whilst increasing performance of the CPU, GPU, screen, and battery. In an ideal world, the chips would be designed to utilize less power, but this can be expensive, so it is often more cost-effective to have higher performance with higher output power.
The miniaturization of devices and their components makes cooling more difficult. Many consumer electronics cannot have active cooling and for those that do, hiding the vents for aesthetics and keeping fans quiet is becoming increasingly important, especially for new devices like VR headsets, where the device is very close to the user. The major pain point highlighted by Meta for new materials to enter the market is cost and validation. Many materials currently used have a long history of application and are low cost; this means a new material has to provide a significant benefit to device performance to even be considered.
A new material for the smartphone market was presented by W.L. Gore. It has developed a thermal insulation material made from PTFE and silica aerogel. This outperforms the air gap typically used for insulation and prolongs the time for hot spots to build up on the device surface and the subsequent performance throttling. A potential driver for the materials adoption is 5G, where thermal insulation is required, but the material cannot interfere with the notoriously sensitive 5G signal.
Summary of the Thermal Management Expo 2022
The event provided insights from several OEMs and material suppliers in the thermal management market. The focus of many suppliers was certainly on EVs, thanks to the rapidly evolving and growing market that provides huge opportunities across the supply chain. However, there was also a significant drive towards other markets, such as data centers, consumer electronics, and a deep dive into the materials and material fillers across various applications. To help better understand these evolving markets and their thermal management requirements, please see the thermal management portfolio from IDTechEx, including Thermal Interface Materials, Thermal Management for Electric Vehicles, Thermal Management for 5G, and Thermal Management for ADAS.