Breakthrough EV battery enclosure is 60% lighter and 15% eco-friendlier

Researchers from the Fraunhofer Institute for Machine Tools and Forming Technology (IWU) achieved an breakthrough in electric vehicle (EV) battery manufacturing. They gave the EV battery enclosures a serious update to reduce the battery’s carbon footprint.

As a result of an initiative involving 15 partners, the COOLBat project focused on “enclosures,” or the battery case in an electric vehicle, to cut carbon emissions by 15 percent in its manufacturing process.

“The principle is simple: the lighter the enclosures, the greater the range of electric cars, as power consumption decreases,” Rico Schmerler, the project manager and scientist says. They employed lightweight construction methods and increased functionality in a smaller space with fewer interfaces, thereby reducing excess weight and carbon emissions.

“By making the enclosure lid out of a fiber composite material, we were able to reduce the mass by more than 60 percent compared to the reference out of steel.” They made it recyclable, too, so the enclosure lid can be reused. And these researchers are only getting warmed up.

EV battery 2.0?

Researchers combined various systems that normally operate individually to create a more energy-efficient design that is 100% reusable. First, they developed a new flame-retardant coating made of lignin, a plant-based material. This coat, which is to be applied on the underside of the enclosure lid, protects the battery from fire and is meant to replace petroleum-based materials.

Then, to better protect the battery for overheating, researchers incorporated cooling channels directly into the load-bearing structures such as cross beams. They also combined the cooling unit function with underride protection in a “base plate,” an innovation developed by Fraunhofer IWU and FES/AES.

Inside the base plate, aluminum foam “absorbs the impact energy for stone impacts and accidents.” A special kind of wax, a phase-change material (PCM), is added to the mix to provide better insulation. In other words, it takes less energy to cool the battery. Fluid flows through the channels, effectively cooling battery cells from all sides, not just from below, as previous models did.

“We’re focusing on functionally integrated structures. Tasks that used to be handled by different modules inside the battery are being integrated into a single component — the base assembly, in this case — to shrink the installation space and streamline interfaces,” Schmerler explains. “These base plates will protect from overheating and avert damage to the battery core in case of an accident.”

Furthermore, the heat that the batteries give off affects the exterior shell, significantly impacting an electric vehicle’s performance and lifespan. So researchers replaced heavy, unsustainable conductive pastes with eco-friendly materials for the EV battery enclosure.

The Fraunhofer Institute for Surface Engineering and Thin Films IST used “a plasma process to metalize open-pored reusable foams that are then placed in pad form in the spaces between the battery and enclosure.”

The electric vehicle just got a serious update

They designed the entire system—the lid, frame, and base plate —not only for reuse but to help the electric vehi cle live up to its purpose: to be an energy-efficient machine.

“We are pursuing the concept of a circular economy and material reduction through lightweight construction and reusable materials, which in turn results in a smaller carbon footprint and lower repair costs,” Schmerler says.

The EV battery enclosure project intends to improve larger systems in the future, such as those in trains, aircraft, and boats.

The press release concludes that the cooling systems could also be used for transporting food and medications, and the fire protection solutions could be used in buildings.