Diving into air-cooled long-range batteries

How Mercedes-Benz ditched water cooling and used trick aero to maximise the utility of new EV powertrains

- CAMERON KIRBY

WHILE THE INEVITABLE TECTONIC movement of progression is pitting internal-combustion engines and battery-electric drivetrains against each other, the two battling forms of automotive propulsion share a number of surprisingly similar qualities.

Each needs careful management to get large amounts of power to the ground, and when engineers crack the code to unlocking greater efficiency, larger outputs are never far behind. That’s why it’s not hard to see the perfromance potential in the Mercedes-Benz EQXX concept, which is ostensibly a hypermiling EV that will be used by the German brand as a powertrain development tool for future electric models.

There’s no shortage of intriguing technological advancements with the EQXX, but what has us at MOTOR particularly interested is the battery system and its unique form of cooling.

Range, not outright power, was the ultimate goal for the EQXX, which Mercedes claims it has achieved by being able to drive the car a huge 1000km on a single charge.

It’s not simply a vast battery either, with the unit slotted between the EQXX’s wheel arches having a 100kWh capacity – fairly regular for modern EVs.

Demonstrating the link between efficiency and power, Mercedes commissioned its High Power Powertrains (HPP) - yes, the F1 engine division - to lead the charge on the EQXX.

Batteries, like combustion engines, need to be cooled when operating. Traditionally this is done with liquid.

The prevailing method of battery cooling is a ‘jacket’ which encases the entire unit and pumps liquid around it to keep temperatures in check.