Thermal Management in Modern Automotive
Combustion engines once generated the majority of the heat in cars. But they’ve been overtaken as electronics technology and green energy have become a focal point for the industry, whether it’s electric vehicle batteries (e-mobility) or increased processing power for safety-based features generating more heat.
There are a few key areas to focus on in the modern automotive industry to ensure effective thermal management.
E-mobility and Car Batteries
In recent years, e-mobility has become a disruptor in the automotive sector as an increasing number of customers turn to electric vehicles and governments start to discourage the use of traditional modes of transport. Once a niche market, e-mobility has rocketed into the mainstream thanks to an increased level of understanding and appetite for more sustainable approaches.
In 2019, global sales of electric vehicles topped two million for the first time, more than double the volume sold in 20171. And as governments across the globe set targets for reducing emissions on the roads, it’s a figure that’s only going to rise in years to come.
For manufacturers, the challenge is making sure these vehicles can deliver the performance customers want, alongside ensuring they are as reliable as possible. Some sticking points of early vehicles included slow charge times and short ranges. These needed ironing out.
E-mobility batteries now require a lifespan of 15 years or more as standard. And they need to be able to deliver consistent fast-charging performance throughout their operational life. On top of this, electric car batteries must also have a higher capacity than ever.
Effective battery thermal management is important for e-mobility batteries for three main instances:
- Normal operation of the car – To slow down the ageing process of Li-ion cells and batteries, which can otherwise reduce their storage capacity.
- Fast charging – Consumers demand quick charges so they can get on with their daily and working lives with as little inconvenience as possible.
- Crashes and accidents – If a cell is punctured, it can catch fire and trigger its neighbouring cell to heat up, causing a thermal runaway. Thermal propagation prevention is important here to reduce the impact.
E-mobility and Power Converters
For automotive designers and engineers, working with a greater density of higher-voltage components than they have previously is a challenge, potentially increasing the chance of overheating and failure. They also need to increase capacity without putting added strain on the battery itself.
Thermal management is also an important consideration for power conversion components like OBC. This includes for:
- Fast charging – Thermal management is more important for power converters than the battery when it comes to charging quickly, as the main heat is released in the power conversion component.
- Crashes, accidents and short circuit – Electrical insulation, which is generally incorporated into thermal interface materials, is vital so the passenger doesn't get a shock if the power conversion component fails.
Thermal management is therefore a vital consideration to ensure modern electric vehicles can effectively balance performance with longevity, reliability and safety firmly in mind. And with the projected number set to grow in years ahead, thermal management in electric vehicles is only likely to become a more prominent consideration.
Driver Safety and ADAS
Safety has also become an important consideration for manufacturers in recent times. For many years, an infotainment system was the most prominent electronic device in most vehicles. But a rising concern for safety and convenience from consumers has seen Advanced Driver Assistance Systems (ADAS) become more common in vehicle design and manufacture.
Data shows that ADAS is growing in popularity every year.
- Between 2015 and 2020, the global market for ADAS grew from $7.64 billion to $17.57 billion.
- It’s expected to continue this trajectory for years to come, hitting over $30 billion by 20232.
But as the demand for such systems increases, so too does the strain this puts on thermal management. Reversing and braking systems, radars, and cameras add exponentially to the operational complexity of vehicles. This means more heat is being generated within these than ever before. And with this increased heat comes a higher chance of failure, which can greatly impact on safety.
If that heat generated by complex computer components within ADAS devices is not properly removed from the source, it can cause the component to fail. This could be a dip in performance or a complete breakdown. This not only creates reliability issues, but it can also lead to increased danger for road users when safety precautions are out of action.
Other factors increase the need for efficient thermal management across power conversion and automotive electronic components. These include:
- Miniaturization – Smaller component sizes leave less space available for use as a heat sink.
- Systems integration – Increased functionality in one system.
- Powerful processing and functionalities – More heat is generated as processing power increases.
To ensure maximum functionality, safety and performance with minimal impact, effective thermal management is therefore a vital consideration. And with the autonomous vehicle market expected to be worth over $60 billion by the end of 20303, the volume of ADAS devices within vehicles is only likely to grow, expanding that need for effective dissipation of the heat they generate.
Why Thermal Management Matters in Automotive
The main function of thermal management for the automotive sector is heat dissipation. More power and higher voltage means an increased amount of heat generation in an increasingly cramped space below the hood of the vehicle.
With so much heat concentrated in a small area, both the safety and reliability of the vehicle can be impacted if this latent heat is not effectively moved from the components that generate it to heat sinks.
Breakdowns can be costly and damage the reputation of manufacturers. So it’s vital that automotive manufacturing is done with an eye on keeping things running as efficiently as possible.
Performance matters in automotive, particularly as cars get ever more functional and powerful. The right thermal management strategy helps ensures vehicles perform on a number of levels, including:
- Reliability and functionality – Thermal interface materials need to effectively dissipate heat in powerful devices and components, both now and through multiple years of regular use, delivering a reliable lifetime performance.
- Convenience and cost-effectiveness – The right material seamlessly becomes part of the production process without slowing down manufacturing in a high-demand industry. It needs to be easy to dispense and integrate into the assembly process in a cost-effective way.
- Overall performance – Thermal performance is only one consideration when choosing thermal interface materials. It’s also vital that the materials live up to the dielectric, mechanical and physical requirements of an existing process.
In newer cars, particularly those with electric batteries, power conversion systems and extensive ADAS equipment, malfunctioning parts caused by overheating and poor thermal management can have further reaching problems too.
For example, if heat is not effectively dissipated in a high-power e-mobility battery during the fast charging process, the battery can overheat and stop working, or even catch fire.
Similarly, if overheating in the central CPU of a car’s ADAS system occurs, reversing cameras and parking sensors can shut down. This can cause significant safety concerns for the driver and other road users.
Henkel’s Automotive Thermal Management Solutions
At Henkel, we know that one solution doesn’t work for all processes. That’s why we work with designers, engineers and process managers to work out the most effective thermal management solution for every component you deal with, however demand is changing your designs.
We take on board the required performance level of the component, its role in the dissipation process and what product gives it the best chance of achieving those goals. These could be GAP PAD® thermal interface materials that eliminate air gaps, gap fillers that combine thermal performance with easy dispensing and speed of process for batteries, or underfills for cameras and other ADAS applications.
Learn more about the impact of heat on electronic components and how Henkel can help you choose the right product for your needs on the insights blog.
Check out the full range of Henkel thermal interface materials to find the right solution for your automotive manufacturing process. Or get in touch with our experts below for unrivalled insights and advice on choosing the right solution.
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