Eberspächer develops third-gen high-voltage heaters for EVs: compact, lightweight, economical

Hybrid and electric vehicles are on the rise, particularly in the developed markets and economies. With intelligent series solutions for electric heating, German supplier Eberspächer catem says it provides the most important models in the world for the right balance between comfort and range. Currently the company already makes the third generation of devices, which sets new standards again especially in terms of weight and space.

In recent years, the number of E- and hybrid vehicles has grown steadily. One important factor here is to improve the traction battery at lower prices. The EU-wide from 2020 CO2 fleet objectives drive the hybridization progress on the streets. According to Dr Klaus Beetz, CEO, Eberspächer Climate Control Systems, "As of today, we have already equipped more than 200,000 electric vehicles with our high-voltage heaters."

Already the first mass-produced electric vehicles Nissan Leaf, Chevrolet Volt and Opel Ampera went with PTC solutions from Herxheim at the start. Meanwhile, the first and the second generation of devices have been proven in all major projects around the world as an ideal heating system for hybrid and electric vehicles. The latest additions to the circle of serial Stromer – e-Golf and e-up! from Volkswagen – catem put on thermal management of Eberspächer. "We expect that this positive international trend to continue with promising prospects for our PTC heater," says Dr. Beetz.

Eberspächer catem has for over 15 years developed intrinsically safe PTC heating systems for automotive applications. Due to the physical properties of the PTC ceramic overheating is reliably excluded, this can only be heated to a certain temperature, after which the PTC automatically reduces the power consumption. This systemic safety factor in all automotive applications, particularly in the sensitive high-voltage environment of electric vehicles, is crucial.

Minus 30 percent: When less is more
With the upcoming high-voltage water heater, the third generation of this successful model is before the series start in 2016. "In addition to the requirement to make heating systems for electric and hybrid vehicles are completely safe and highly efficient in battery vehicles and plug-in hybrids in particular the weight and space are an issue," says Dr Beetz. Already the current version is one of the most compact high-voltage water heaters on the market. Extensive development has been able to reduce the volume and weight of the next generation of devices by 30 percent. In addition, the manufacturing process is greatly simplified through numerous optimizations. "With the third generation of our high-voltage water heater for electric vehicles, we can for our customers numerous advantages in terms of weight, installation space and costs generate," says Dr. Beetz. The update is based on the extensive expertise of the system Eberspächer subsidiary, which also includes the area of intelligent power control. Integrated electronics provide – in addition to the PTC heater – for efficient energy and heat management.

The high-voltage PTC heater from Eberspächer catem is designed for different drive concepts. In pure electric vehicles, the high-voltage air heaters provide fast for the right comfort. If the vehicle has its own water cycle – such as large electric and hybrid vehicles – high-voltage water heaters are used, the proposed via the heat exchanger in the vehicle tempered air into the interior.

Air heater Innovation for 48-volt electrical system
Electric heaters play a key role in the further development of vehicles with electrified drive technologies as they compensate for the resulting caloric deficit. An important development in this area is mild hybrids with 48-volt electrical system. Since it can save up to 20 percent fuel with this form of car electrification compared to purely IC engine-driven models in city traffic – and at relatively low cost – is to be expected with a correspondingly rapid spread of technology.

Conventional PTC air heater as well as the necessary relays, however, are designed for 12-volt electrical system and would need to be adapted to the 48-volt electrical system. A solution has catem the innovative Integrated Switch (IS) PTC heater from Eberspächer. The built-in heater circuit element replaces the functionality of the external relay and is already prepared for use in 48-volt power. With its compact design, the IS PTC heater can replace the current 12-volt PTC air heater problems and offers significantly more functionality in the same space. The integration of the relay functions in the heater also reduces the work required for installation and wiring considerably.