VEHICLE CABIN HEATING
One of the most important features of an electric vehicle (EV) is its energy consumption and the resulting range. Especially during cold days, heating becomes very important. Combustion driven vehicles have a lot of waste heat available, which is partly used for heating up the cabin to thermally manage the driver, co-driver and the passengers. In contrast, electric vehicles, don't produce so much waste heat anymore. Even not close to it. But the requirement for establishing and maintaining thermal comfort is of same importance than for combustion driven vehicles.
Today, a vehicle cabin is heated up while blowing warm air into the cabin until certain temperatures are reached. This process is very inefficient, because:
- During very cold conditions, due to humidity issues, a vehicle is mostly heated up in fresh air and not in recirculation mode
- Producing warm air takes a while and is not available from "ignition on"
- Warm air always tends to rise up due to buoyancy effects
To compensate for this and to make a heating system much more efficient, transferring heat through radiation is much more efficient. To do so, different surface elements of a vehicle cabin can be equipped with heating elements, which heat up the surface parts up to a level, which can contribute to thermal comfort.
We offer two different variants of different integration methods:
- Integration in soft surfaces
- Integration in hard surfaces
Integration into soft surfaces
The integration in soft surfaces is widely used today. Example for this kind of integration is a heated armrest or a heated middle arm console. Today, heated wires integrated into non woven materials are mostly used for this purpose. Our printed silver heaters are a real alternative to this commonly used method. Printed silver heaters have a few advantages compared to wire heaters:
- Printed silver heaters don't have to be heated up above the desired temperature level (they are no "line-heaters" like wires)
- Printed silver heaters are area heaters, allowing for a very fraction of heated area on a given surface
- Printed heaters can be large in size
- The cost of (especially) larger printed heaters are much lower due to the nature of the involved production processes
We offer different variants of heating elements to be integrated into soft surfaces:
- Printed Silver Heaters without PTC effect
- Printed Carbon Heaters with strong PTC effect
Whereby the printed Silver Heaters are an alternative to the wire based heaters, PTC-heaters open up new possibilities. These heaters can't become warmer than the predefined maximum temperature. Even when certain areas of a heated surface gets thermally insulated, the heating element will not be possible to become warmer than the intrinsic maximum temperature. This maximum temperature can be either used as normal operation temperature, which will be reached and maintained even without electronics, or as intrinsic safety feature. Any temperature below maximum can be realized while PWM control other similar methods.
Integration into hard surfaces
Integrating heating elements into hard surfaces allows for the thermal management of many different components which are part of the vehicle interior. Examples are:
- Instrument Panel
- Glove box
- Steering wheel cover
- Door trim panels
- A, B or C-Pillar
Here we also distinguish between classical printed Silver heaters and the carbon based heaters with an intrinsic strong PTC-effect. Normally, the heater structure is printed on a certain base material, which later on is directly inserted into the tooling of the plastic part. The heating element will then be back-injection molded, making it an inseparable part of the plastic component. With an ATT Patent protected method, a necessary electrical connector will be produced simultaneously to the injection molding process.
We believe that the integration of heating elements into hard surfaces will be the next evolution step in a more systemic approach of thermally managing the vehicle cabin in context of maximizing the range of electric vehicles. If you are of the same opinion than we are, why don't start a conversation about we could possibly work together on this topic?
How to work together with us?
ATT is your strategic partner and also one-stop-shop for vehicle cabin heating strategies. We not only support you in specifying the heaters, but also design, develop and manufacture them for you. But we are necessarily not limited to Automotive. So far, we have supported numerous customers in Rail and also Aerospace industry in finding the right solutions for their challenges.
We are also happy to support our partners in research driven projects. Please feel free to contact us with your requirement, idea or ready-made RFQ.