Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Electromobility: Laser-Based Processes for Lightweight Battery Packs

09.09.2015

By continuing to develop the electrification of powertrains, researchers are looking to the future of mobility in economic and environmental terms: indeed, electric mobility provides valuable solutions for the automotive industry as it implements climate change objectives. Thanks to lightweight materials, the weight of the vehicles can be reduced significantly, thus increasing their operating distance. Within the framework of the joint project »Fraunhofer System Research for Electromobility II«, the Fraunhofer Institute for Laser Technology ILT has developed processes for the production of lightweight battery packs that significantly contribute to the reduction of CO2 emissions.

At the 66th International Motor Show IAA in Frankfurt, Fraunhofer ILT will be presenting the joint project »Fraunhofer System Research for Electromobility II« along with 16 other Fraunhofer institutes from 15 to 18 September 2015. Using the example of a »Lightweight Battery Pack« they will demonstrate to visitors how production technologies for lightweight construction can assist in storing the energy to power vehicles. They will be showing three different and partially complementary process technologies.


Lightweight battery pack: a combination of high-strength steel and fiber reinforced plastic.

© Fraunhofer ILT, Aachen


Battery block with hermetically sealed laser welded battery cells (Type 18650).

© Fraunhofer ILT, Aachen / Klaus D. Wolf

Laser-beam cutting and welding

For the processing of high-strength steel, it is important to avoid excessive thermal influence and, thus, material damage. Since they have such a small heat-affected zone, laser cutting and welding are particularly well suited here. In addition, these processes are economically more efficient than the traditional metal-cutting processes, since no material wear occurs.

“This process is already being used by Volvo. What is new here, however, is the combination of a plastic/metal compound for use in the car body, which we are presenting to the automotive industry for the first time. Thanks to the connection to the plastic, less steel is required in the application. Higher strength is achieved and the battery case is lighter. Through this process, we ensure that the industry can exploit the full potential of lightweight high-strength steel,” explains Dr. Alexander Olowinsky.

Joining plastic and metal

As an alternative to the conventional adhesive bonding of multi-material composites, Fraunhofer ILT will present a laser-based process of connecting simple semi-finished products, organic sheets, with metals such as high-strength steel. This process can, for example, be used in lightweight automotive construction as well as in the fields of mechanics and small components.

In the two-step method, a continuously emitting fiber laser at high speed first generates a microstructure in the metal. The structures have an undercut and are 30 µm wide and about 100 µm deep. In the subsequent joining step, the plastic is pressed against the structure and heated up to the molten phase of the matrix material. The matrix material then flows into the microstructures and locks into the undercut structures. The result: the connection is highly robust and an additive is unnecessary.

Reproducible and safe: oscillation welding for the electrical connection of battery cells

To construct complete battery packs, the Aachen researchers rely on oscillation welding with laser radiation. Here, individual battery cells (type 18650), which are normally used in power tools and notebooks, are welded together with copper contacts, therefore providing an electrical and thermal connection. The remarkable thing is that the joining at the negative pole also takes place from the top of the cell.

In a parallel circuit of 30 cells, a tight space between the battery cells is created by the design of the module and filled with PCM slurry (Phase Change Material, a mixture of paraffin and water). “By using the PCM, we are able to protect the battery cells thermally. This ultimately extends battery life,” says ILT researcher Benjamin Mehlmann. The use of laser-beam oscillation welding leads to a better control of the welding and, thus, a stable process. Moreover, the method is qualified and suitable for industrial mass production, for example, for the production of power tools.

Strengthening the German economy

Together, these three process technologies are especially suitable for the large-scale production of traction batteries for vehicles, for example, as the processes are highly automated and the energy input is easy to control. Since the market for these vehicles is steadily growing, this process development has a very promising future.

“In order to advance the battery production in Germany – currently most components are bought from abroad – our processes have to be automated, robust and less expensive. We are pleased that we can make a decisive contribution towards the production of lightweight battery packs and battery modules in Germany,” said Dr. Olowinsky.

Presentation of the lightweight battery packs at the IAA

What makes the lightweight battery pack special is that it is modular: the so-called traction batteries are suitable for hybrid vehicles as well as for use in electric vehicles with higher operating distances. Fraunhofer ILT is coordinating the subproject »Lightweight Battery Pack« within the »Fraunhofer System Research for Electromobility II«. The Fraunhofer Institute for Environmental, Safety and Energy Technology UMSICHT is managing the use of the PCM slurry for buffering the thermal energy.

The electric control and the battery management system have been developed by the Fraunhofer Institute for Solar Energy Systems ISE. The assessment of the plastic-metal compounds was carried out by the Fraunhofer Institute for Mechanics of Materials IWM, which used simulation and load tests to examine the mechanical design of the battery case.

First results of the crash tests as well as the entire demonstrator model of the lightweight battery packs will be shown at the joint Fraunhofer stand D33 in Hall 4.1.

Contact

Dipl.-Ing. Benjamin Mehlmann
Micro Joining Group
Telephone +49 241 8906-613
benjamin.mehlmann@ilt.fraunhofer.de

Dr. Alexander Olowinsky
Head oft he Micro Joining Group
Telephone +49 241 8906-491
alexander.olowinsky@ilt.fraunhofer.de

Fraunhofer Institute for Laser Technology ILT
Steinbachstraße 15
52074 Aachen, Germany

Weitere Informationen:

http://www.ilt.fraunhofer.de

Petra Nolis | Fraunhofer-Institut für Lasertechnik ILT

Further reports about: Electromobility Energy IAA ILT Lasertechnik battery construction oscillation plastic structures technologies vehicles

More articles from Trade Fair News:

nachricht BAM@Hannover Messe: innovative 3D printing method for space flight
24.04.2018 | Bundesanstalt für Materialforschung und -prüfung (BAM)

nachricht Clean and Efficient – Fraunhofer ISE Presents Hydrogen Technologies at the HANNOVER MESSE 2018
23.04.2018 | Fraunhofer-Institut für Solare Energiesysteme ISE

All articles from Trade Fair News >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: BAM@Hannover Messe: innovative 3D printing method for space flight

At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.

Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...

Im Focus: Molecules Brilliantly Illuminated

Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.

Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Getting electrons to move in a semiconductor

25.04.2018 | Physics and Astronomy

Reconstructing what makes us tick

25.04.2018 | Physics and Astronomy

Cheap 3-D printer can produce self-folding materials

25.04.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>