Electric vehicles promise significant advances for future mobility — making driving safer, more efficient and more convenient. Electrically powered vehicles emit lower direct emissions, for example.
At the same time, they permit the use of electricity from renewable energy sources. However, the success of new mobility concepts depends to a significant degree on the car drivers themselves. They have to accept the fundamental concept and trust the technology used. It is precisely this acceptance that is still the sticking point at the moment. The reasons for this are the high purchase costs and short ranges, but also environmental aspects, such as a high level of energy and raw materials consumption during the manufacture and disposal of the batteries.
This requires a sophisticated thermal management system. The hose and pipe systems are correspondingly complex. Continental already supplies solutions for the cooling system that the manufacturers can straightforwardly install themselves. The lines for the battery cooling system in hybrid and electric cars laid in the underfloor section of the vehicle, for example, are almost 4 meters long. They ensure that the units do not overheat, the batteries achieve their maximum lifetime, and the occupants do not have to forgo the level of warmth to which they have become accustomed. Unlike conventional vehicles, electric vehicles require two cooling circuits. Water, which is the most commonly used cooling medium, cools power components such as the motor and electronics, on the one hand, and the battery, on the other. The battery achieves its maximum service life at temperatures between 10 and 30°C. It therefore makes sense to supplement the water or oil cooling system at high thermal loads using the air-conditioning system’s refrigerant circuit. A new connector enables Continental to minimize pressure losses in this process.
The weight of the new hose generation has also been reduced. Smaller line cross-sections on the high-pressure side and in the battery cooling line help to ensure that as little refrigerant as possible has to be used. The right mixture of rubber, polyamide and aluminum materials and an ingenious line geometry ensure the system has adequate inherent stability. The hose developers succeeded in reducing the weight of the oil cooling line by 25 percent, while improving its under- and overpressure resistance by 50 percent at the same time.
In addition, Continental has developed hose lines for battery tempering using oil instead of water as the coolant. Since oil does not have any charge carriers, this rules out any short-circuits which could result in a total failure of the battery. This even means that the battery can be completely immersed in oil. As a result of its insulating effect, therefore, it reduces the impact of outside temperature action and thus also the need for regulation.