Direct cooling is the way forward.
When the first car with an internal combustion engine appeared on the scene over 130 years ago, it could barely crawl up a hill, and now the same technology can get a Bugatti Veyron to over 250 mph. While ICE technology has had over a century to develop, electric powertrains are still playing catchup. But this burgeoning technology is quickly getting up to speed, and many EVs are already offering ranges of over 300 miles. Companies such as BMW believe that a range of around 370 miles should be enough, but cars such as the Lucid Air Dream Edition have pushed things past the 500-mile barrier, becoming the longest-range electric vehicle in the process. To extend those figures even further, oil and gas giant Petronas believes cooling fluids are the key.
Unlike traditional ICE-powered vehicles which require a slew of different oils and liquids to keep it cool, electric vehicles can do without many coolants such as water and glycol, or motor oil. EV vehicles do still require certain areas to be kept at a reasonable temperature, including the gearbox and battery pack. In the EV industry this is called thermal management. Petronas is currently at the forefront of developing dedicated EV fluids, and is starting to shift the focus away from indirect to direct cooling solutions. Indirect cooling uses heat sinks to draw away heat from the source and circulate it with coolant. According to Petronas this system is rather inefficient as not all of the heat gets drawn away; some of it has to escape by other means. Direct cooling, as the name implies, makes direct contact with electrical components such as copper and plastic parts, and circuit boards. We all know that liquids and electronics don't mix well, that's why the direct cooling liquid is dielectric (it doesn't conduct electricity).
When EV drivetrains become integrated, not only does this liquid need to cool components, but also lubricate moving parts. With the correct cooling liquid, charging times will be improved. Currently, cars capable of 350-kW charging see a dramatic throttling of current after peak thermal efficiency is reached to prevent damage. Petronas says that in theory, cars such as the Porsche Taycan will be able to fully charge in 16 minutes, instead of the standard 41 minutes if direct liquid cooling is properly implemented. So it turns out that the future of EVs is more than just building more efficient batteries. Exciting times indeed.