Battery systems in electric vehicles face demanding environmental, mechanical, and chemical requirements. In addition to these requirements, vehicle designers are being asked to emphasize safety and weight reduction. These demands drive their search for battery-related materials that are lightweight, inexpensive, flame retardant, and meet rigorous electrical insulation requirements. These requirements extend to the battery cover material, which must not only serve reliably as an electrical barrier, but also meet an OEM’s targets for original cost, and maintenance costs under service agreements.
While electric vehicle battery requirements are similar to those for cars with only internal combustion engines, there are some differences in these two applications. Perhaps the most striking differences are the much larger size of electric vehicle batteries, and where they are located in the car. Conventional car batteries located in the engine compartment typically use only small covers over two battery terminals. Electric vehicles typically use many batteries with their terminals strapped together to get the drive voltage and current needed for the car motor. This means the battery cover must be larger. In addition, an electric car battery system could be placed in different locations depending on vehicle design. This has implications for the shape and other requirements placed on an electric vehicle battery cover.
When ITW FormexÂ® looked at these battery cover requirements, company engineers saw that its FORMEXâ