Lightweighting: A New Approach to Battery Enclosures

September 22, 2021


Lightweighting isn’t a new idea in automotive – in fact, the concept has been discussed for almost 70 years. In 1953, 300 Chevy Corvette cars were produced using fiber reinforced plastic body panels.* Kautex joined the lightweight revolution 11 years later in 1964 with its first all-plastic fuel tank produced for Ford Motor Company – and we’ve been working with our customers to reduce weight and improve packaging options ever since.

With the transformation to electric vehicles (EV), lightweighting takes on a whole new level of importance. On average, a battery pack accounts for about 75% of the total electric powertrain weight,  leading to a pack-to-vehicle weight ratio of 20 – 30%. These high ratios quickly negate any efforts previously made to reduce the overall weight.

Just as a heavy truck typically has lower gas mileage than its economy-sized counterpart, in the same way a heavy BEV vehicle may have less range and require more frequent charging or, in the case of a plug-in hybrid, more use of the internal combustion engine to drive the car in-between charging.


Kautex’s new battery enclosures made from thermoplastic composite or a composite-metal hybrid helps OEMs tackle this “weighty” topic. Our solutions offer up to a 60% weight reduction compared to traditional steel enclosures. When compared to aluminum housings, the Kautex solution is still up to 20% lighter.

How can Kautex’s lightweight solution benefit the OEM and what benefits does it bring to the end consumer?

  • Improved logistics: Lightweight battery packs/enclosures allows you to place more packs into the truck before reaching payload capacity – and help with in-house logistics as well.
  • Further reduce the weight and cost by removing cell material: While less weight means OEMs can decrease the battery size, it will also result in reduced range of the vehicle. Some OEMs opt to keep the range at the current level, but take out cell material from the battery pack, further reducing the overall weight the of pack and reducing cost.
  • Optimize vehicle design: Reducing battery pack weight allows OEMs to adapt the brake system, suspension and crash structure.
  • Sustainability in your logistics chain: Less payload means less fuel consumption, less brake and tire wear – and less air pollution from the micro-particles created by the wear on the tires and brakes. In fact, recent studies of tire particulates show that “tire wear is the second largest pollution source in our oceans after single-use plastics….”1
  • Reduce axel weight: Plug-in hybrid vehicles face an additional challenge in that the heavy battery system means the vehicle can quickly reach its maximum axel weight. To compensate for this, OEMs must incur a costly development process to reinforce the axels or reduce the payload for the end customer. By reducing the weight of the battery enclosure, Kautex offers the OEM the opportunity to add weight elsewhere in the vehicle before reaching the maximum axel weight.
  • End-consumer benefits: Reducing the weight of the battery housing can result in increased maximum payload and/or increased drive time between charging cycles, decreasing ‘range anxiety’.

Interested in learning more about Kautex’ lightweight battery enclosures for the EV segment?  Email