Battery Testing

In our Lab Battery Testing, we provide performance testing for battery cells and systems regarding efficiency and effectiveness, aging tests as well as safety and reliability tests.

Our Services include:

  • Battery test facility for testing small and large size battery cells up to battery systems
  • Battery aging: calendaric and cyclic
  • Performance: efficiency and effectiveness
  • Reliability under a wide range of operating and aging conditions
  • Validation of technical and functional safety
  • Development and evaluation of methods to prevent thermal runaway and propagation
  • Non-contact quality determination and assessment in battery cell production
  • Non-destructive defect localization in battery cells
  • Mechanical measurement and evaluation of battery cells and modules under pressure/compression

Aging Studies

For the investigation of aging and lifetime of battery cells and battery systems, we offer long-term tests with our equipments for cells, modules and systems at different voltage levels. These include both cyclic and calendar aging analysis as well as determination of the application-specific remaining useful lifetime. The most important parameters are the change in capacitance, internal resistance, heat dissipation and mechanical expansion. We provide scientific support for the tests and advise you on the test design.

Our laboratory equipment includes battery testers for cells, modules and systems, impedance spectroscopy and calorimeters.  The tests are carried out in the climatic chamber or in air-conditioned rooms according to standards or customer requirements.

The range of services offered by our laboratories also includes destructive tests using mechanical, electrical and thermal mishandling. For this purpose, electrodynamic shakers, separate shockers, crush, short-circuit and nail penetration tests are available. These tests can also be thermally superimposed.

Battery Testing: Test facility for battery cells
© Fraunhofer ISE
Test facility for battery cells with over 400 test channels.
Battery Testing: Climatic chambers for battery test objects
© Fraunhofer ISE
Climatic chambers for battery test objects of various sizes.
Battery Testing: Scientific monitoring and evaluation of our tests
© Fraunhofer ISE
Scientific monitoring and evaluation of our tests.

Characterization, Testing and Destructive Testing of Batteries for Quality Assurance Purposes.

With the continuous rapid development of the battery market, especially in mobile and stationary applications, the need for repeatable examination and testing of cells and systems continues to increase significantly. Flaws in battery design (both at cell and system level) can lead to either reduced performance and financial losses or even critical damage and accidents. Established test methods and novel characterization capabilities in the test lab can identify defects at the cell level as well as in the system structure and in the system design at an early stage.

To pursue this goal, we offer battery testing from cell to system level, according to customer specifications or according to established standards (e.g. UN38.3, IEC 62133, IEC 62619; IEC 62841). Furthermore, we provide support to our customers in the research of aging effects and in the development of application-oriented measures for lifetime optimization. Our modern equipment guarantees a reliable and safe operation of the battery tests.

Damage analysis of defective batteries
© Fraunhofer ISE
Damage analysis of defective batteries.
Drop test of a Powertool battery as part of misuse tests
© Fraunhofer ISE
Drop test of a Powertool battery as part of misuse tests.
Destructive testing, e.g. overcharge tests of battery cells in shelters
© Fraunhofer ISE
Destructive testing, e.g. overcharge tests of battery cells in shelters.

Crush Testing: Destructive Testing to Optimize Battery Safety

With our battery tests, we examine various scenarios to which batteries are exposed during their use. We place a special focus on situations that deviate from everyday use in conformity with the intended purpose. For example, a crush test can be used to test the penetration of a foreign object into a battery as well as the crushing and bending of a battery. Such a test can provide important information about battery behavior in the event of accidents and mishandling. Especially when used in e-vehicles, the issue of battery safety is of crucial importance.

By means of our detailed analyses, we are able to provide battery manufacturers with valuable assistance in optimizing battery safety.

By using customizable crush profiles, we can perform standard tests and - in addition - flexibly tailor our tests and measurements to the specific requirements of our customers. During a crush test, with up to 32 voltage and temperature channels, accurate monitoring of the DUT can be ensured. Various performance and safety parameters can be determined: Maximum penetration depth as well as maximum compressive force before thermal breakdown and point of stress breakdown.

© Fraunhofer ISE
Crush test of a lithium-ion battery (18650) often used in portable devices (e.g. notebooks, powerbanks) or sometimes in e-vehicles.
© Fraunhofer ISE
During the test, voltage, temperature, penetration depth, speed of the crush profile, and force can be precisely measured.
© Fraunhofer ISE
After thermal runaway, the battery ignites within the protected test environment. In parallel, the collected data is analyzed and incorporated into a detailed test report.

Quality Determination and Evaluation of Battery Cells in the Production Process

Quality control for reliable and high-quality battery cell production is a complex task in which a whole range of relevant influencing variables must be taken into account. The quality of battery cells is reflected in a wide variety of parameters such as mechanical stability, capacity, performance or service life. The reasons for this are the variation in material quality, but also in production processes such as mixing, coating, assembly and formation. This can lead to high scrap rates.

To significantly reduce scrap, production facilities need real-time feedback from the process. We focus on non-contact measurements to locate defects. This enables end-of-line quality assessment of battery cells. In addition to quality determination and assessment in cell production, our measurements and processes are particularly applicable in the context of inspection of incoming goods for battery systems.

The non-contact quality control and assessment helps to identify potential optimization steps at an early stage of production, to minimize reject rates and thus to reduce production costs. To this end, we are developing methods for non-destructive quality control and data-based quality assessment of battery cells that are suitable for use in production lines, for example as part of the project  "OrtOptZelle" funded by the German Federal Ministry of Education and Research (BMBF) in cooperation with RWTH Aachen University. In our battery test laboratories, mechanical, optical, acoustic and electrical methods are used to characterize batteries. Subsequently, these methods are validated by post-mortem analysis, which includes cell opening, characterization of cell components using microscopes, surface and chemical analysis. These results are used, for example, to help optimize battery performance and lifetime through targeted compression on battery cells.

Non-destructive characterization of battery cells and pressure application during operation
© Fraunhofer ISE
Non-destructive characterization of battery cells and pressure application during operation.
An electrode cross-section by scanning electron microscopy as a method of analysis
© Fraunhofer ISE
An electrode cross-section by scanning electron microscopy as a method of analysis.
Post-mortem analysis of battery cells: Opening under inert gas atmosphere
© Fraunhofer ISE
Post-mortem analysis of battery cells: Opening under inert gas atmosphere.

More Information on this Topic:

Research Project


Planning and Implementation of an Innovative Energy Concept for a Development and Test Center for Batteries and Energy Storage Systems in a Distribution Grid for Industry and Electromobility

Research Project


Position-Dependent Compression of Battery Pouch Cells for Lifetime Optimization

Research Project


Development of passive solutions to inhibit propagation in stationary storage systems