Sustainability

Using products

With countries around the world declaring a switch to electric and hybrid cars, which are said to emit less CO2, the presence of automotive secondary batteries is increasing, but at the same time their weight is becoming a major issue. .

Therefore, by incorporating engineering plastics into the design of automotive secondary batteries, it is possible to contribute to weight reduction.

Metal replacement is the act of replacing a metallic component with a similar component made of plastic.

The case study presented here explored a proposal to redesign an existing metal product using plastic materials. A consideration of designs incorporating the results of multiple topology optimizations succeeded in reducing the weight by more than 60% compared to the original metal product; although this exceeded the original goal of 40% weight reduction, it involved an exceedingly complicated mold design, so we attempted to search for further improvements. An additional round of topology optimizations revealed that some portions of the redesigned product were superfluous, and saving these portions simplified the shape of the product and greatly facilitated the mold design—and, as an additional bonus, achieved a weight reduction of more than 80%, far surpassing the original goal.

Asahi Kasei’s XYRON™ modified polyphenylene ether (PPE) resins are non-halogen, flame-retardant engineering plastics whose low specific gravity reduces resin usage and help to achieve sustainability goals. This material offers many excellent properties, such as  dimensional stability, mechanical strength and hydrolysis resistance, and has become a common choice of material for automotive secondary battery cells and structural components, helping to undergird the explosive growth of electric vehicles.

The outstanding electrical properties and tracking resistance of XYRON™ resin have also earned this  material a role in high-voltage solar-power generation systems. The use of plastics with outstanding tracking resistance for high-voltage systems allows miniaturization of products and helps to reduce resource usage. The low specific gravity of these materials also reduces CO2 emissions during shipping.

SunForce™ foams combine the excellent properties that only foams can offer—light weight and thermal insulation—with flame retardance (UL-94 V-0), dimensional stability, and the ability to form products with thin walls. The result is a foam material offering functionality far beyond the capabilities of conventional foams. The foamy structure of SunForce™ beads means that this material contains less resin than solid materials—and, as a consequence, fewer pathways for heat to flow through the material, ensuring low heat conductance and thus high thermal insulation.

A well-known property of batteries is that their output falls dramatically at low temperatures. To avoid this behavior, electric vehicles and high-output hybrid cars have devised various strategies, involving heaters and other mechanisms, for keeping batteries at sufficiently warm temperatures. Asahi Kasei recommends insulating vehicle batteries with SunForce™ beads which may prevent batteries from releasing heat and cooling while the vehicle is at rest, preserving the battery’s high output power for hours with no need for a heater. When heaters are present, the insulation provided by SunForce™ beads may  minimize thermal losses to the outside.   SunForce™ beads also reduce the power used to cool batteries while driving by reducing the influx of outside heat through the vehicle chassis. This improves heat-exchange efficiency and maximizes battery performance.

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The excellent mechanical properties and friction/abrasion properties of polyacetal (POM) resin make it a good choice of material for mechanical components such as gears and axle bearings. Asahi Kasei’s TENAC™ MG210 POM homopolymer is not reinforced by glass fibers or other fillers; instead, Asahi Kasei’s crystal-control technology enables this product to exhibit good mechanical properties and excellent creep resistance, making it an ideal material for gears designed to operate under heavy loading, such as in mechanisms for raising and lowering glass windows in cars.

The excellent mechanical properties and friction/abrasion properties of polyacetal (POM) resin make it a good choice of material for mechanical components such as gears and axle bearings. Asahi Kasei’s TENAC™ MG210 POM homopolymer is not reinforced by glass fibers or other fillers; instead, Asahi Kasei’s crystal-control technology enables this product to exhibit good mechanical properties and excellent creep resistance, making it an ideal material for gears designed to operate under heavy loading, such as in mechanisms for raising and lowering glass windows in cars.

In particular, the fatigue properties and creep resistance of TENAC™ MG210 are not only superior to those of other general-purpose engineering plastics, but even outperform standard POMs (copolymers) and Asahi Kasei’s previous generations of high-durability POMs (homopolymers). We recommend to choose TENAC™ MG210 which may extend the lifetime of your products—and may help achieve other goals as well: miniaturizing gears and other components, reducing product weight by replacing metal with plastic, and decreasing the component count.