battery testing & simulation
To ensure safety, reliability and performance in any situation, we offer battery testing and simulation services as well as the according equipment based on existing industry standards. Furthermore, we can provide calibrated and validated structural, thermal and electromagnetic FE-models to advance your battery specific developments!
abuse testing
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In the field of safety assessment, abuse testing is a critical focus at 4a engineering, where high-capacity cells, modules, and small packs undergo rigorous testing in a controlled environment. The objective is to challenge the cells by subjecting them to extreme conditions, inspired by ARC tests, and utilizing techniques such as gas chromatography to closely observe and analyze their behavior under stress.
material testing
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Comprehensive material testing is a top priority to guarantee the highest standards of safety, performance, and reliability in every battery system, with expert teams thoroughly assessing the materials used in the construction of battery packs, specifically focusing on the performance of barrier materials, fire-resistant components, and battery enclosure materials to ensure optimal functionality and safety under all conditions.
multiphysics simulation
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Multiphysics simulation is an advanced computational method that enables the simultaneous analysis of various physical phenomena. In the context of battery systems, this technique facilitates the detailed examination of the interactions between electrical, thermal, and mechanical effects within the battery cell, providing valuable insights into its performance and behavior under different conditions.
abuse testing
Electrical abuse testing
Electrical abuse testing subjects the cell to conditions beyond its normal operating range, such as overcharging or short-circuiting. This deliberately induces thermal runaway, allowing analysis of the cell's response under extreme electrical stress and assess potential safety risks.
Thermal abuse testing
In thermal abuse testing, high temperatures are applied to induce thermal runaway and assess potential thermal propagation. The testing employs surface heaters, spot heaters, heating wires, and other heating elements to analyze thermal stability and potential safety risks.
Mechanical abuse testing
Mechanical abuse testing characterizes the cell’s behavior under mechanical stress conditions, including crushing, bending, shearing, tab ripping and nail penetration, while investigating the potential for thermal runaway under these extreme and complex physical scenarios.
General testing capabilities and setups
- Conduction of tests with high capacity cells in N2 inerted atmosphere
- abuse testing of modules and packs up to 7.5 kWh
- Gas analysis with gas chromatography using TCD detector
- Detection of all permanent gases and lower hydrocarbon compounds
- H2 - Hydrogen
- CO2 - Carbon Dioxide
- CO - Carbon monoxide
- O2 - Oxygen
- CH4 - Methane
- C2H4 - Ethylene
- C2H6 - Ethane
- C2H2 - Acetylene
- C3H8 - Propane
- C4H10 - Butane
- H2S - Hydrogen sulfide
- N2 - Nitrogen
- Exhaust filter system
- Test execution in closed and safe containment
- Adaptive test setups and engineering of customized setups
- System for prestressing prismatic and pouch cells according to customer specifications
- Max. force level: 100 kN
- Time-synchronized DAQ with a resolution of <500 kHz:
- Temperature: Up to 40 thermocouples can be applied
- Pressure: 3 pressure sensors can be equipped in the setup
- Measurement of the ambient conditions (ambient temperature, ambient pressure, humidity)
- Voltage signal: Cell voltages from up to 6 cells can be recorded
- Time: synchronous time signal
- Force:
- Mechanical test rig with max. 50 kN load cell
- Nail penetration set up equipped with a 50 kN load cell
- Displacement:
- Displacement measurement for the mechanical test equipment with an accuracy of <20 µm
- Displacement measurement for the nail penetration / compression endurance test with an accuracy of <100 µm
- Video recording:
- HD-Video recording with max. 2 HD cameras from outside the TR-chamber
- Max. frame rate: 240 fps
- Max. resolution: 1920x1200 px
- High-Speed camera video recording from outside the TR-chamber
- Max. frame rate: 30000 fps
- Max. resolution: 512x512 px
- Max. frame rate: 80000 fps
- Max. resolution: 256x256 px
- WebCam video recording from inside the TR-chamber
- Max. frame rate: 30 fps
- Max. resolution: 1920x1080 px
- SpyCam HD-video recording from inside test set-ups
- Max. frame rate: 24 fps
- Max. resolution: 1920x1080 px
- Optional modus: Night vision
- HD-Video recording with max. 2 HD cameras from outside the TR-chamber
Overcharge
assessing battery performance under excessive charging conditions
Stats:
- All types of battery cells
- Max. current 210 A (CC/CV)
- Single cell, stacks or module
Over-Discharge
assessing battery performance under excessive discharging conditions
Stats:
- All types of battery cells
- Max. current 250 A
- Single cell, stacks or module
External short circuit
examining battery resilience when faced with potential short circuit scenarios
Stats:
- All types of battery cells
- Short resistance < 5 mΩ
- Single cell, stacks or module
Overheat
triggering thermal runaway through heat induction
Stats:
- Slow heating rates 1-10 °K/min
- Fast heating rates 60-1500 °K/min
- ARC and non-ARC environment
- Ambient temp. 0-80 °C
- local spot heating
- surface heating
Thermal propagation
investigating the propagation behavior of battery systems
Stats:
- Stack or module (all cell types)
- Trigger: electrical, thermal or nail penetration
- Max. energy density up to 7.5 kWh
- Multiple triggers simultaneous / consecutive
Mechanical testing
characterizing the mechanical properties and TR behavior under different load cases
Stats:
- Quasi-static and dynamic (0.1 – 3200 mm/s)
- 3-point bending, crush, tab ripping, shear
- Up to 30 kN and 600 J
- 0 - 100% SoC
- all cell formats and types
Nail penetration
assessing battery robustness and safety when subjected to severe puncture incidents
Stats:
- Displacement controlled load
- Cell and stack level
- Velocity: 0.01 – 20 mm/s
- Max. force: 20 kN
- Max. cell or stack width 300 mm
- Ambient temperature controlled
Compression endurance
evaluating battery performance under prolonged pressure conditions
Stats:
- Max. applicable force 20 kN
- Displacement controlled load
- Cell and stack level
- Max. cell or stack width 300 mm
- Ambient temperature controlled
material testing
material testing
material testing provides a deeper understanding of the materials used in batteries. It helps in identifying potential issues that could affect the performance and safety of the battery, thereby contributing to the development of more efficient and safer batteries.
propagation prevention, encapsulation integrity, fire-resistance
UL 94
standard for classifying plastic flammability, ensuring fire safety compliance
Stats:
- from HB (least) to V-0 (most)
- burn duration after flame removal
- evaluates potential burning droplets
- ratings depend on material thickness
UL 2596
evaluate the thermal runaway resistance of materials used in EV battery enclosures
Stats:
- withstands high temperatures
- maintains structural strength
- resists gas pressure buildup
- weather ejected debris
Torch and grit
evaluate EV battery enclosure materials, simulating thermal runaway conditions
Stats:
- tests heat resistance with a 3 kW flame
- simulates mechanical abrasion
- repeated cycles for durability assessment
- rates materials based on endurance
Customized test setups
we offer tailored battery testing methods to assess safety, durability and performance under real-world conditions
Examples:
- Closed Box Test: Evaluates thermal runaway in prismatic cells within sealed enclosures.
- Material Compression Fixtures: Test clamping and expansion behavior of different materials.
- Multi-Stress Testing: Combines thermal, mechanical, and electrical stress simulations.
- Custom Environmental Chambers: Simulate extreme conditions for battery enclosures.
Expertise Beyond Standardization
Our experts are proficient in industry-standard tests like UL-2596, facilitating direct material performance comparisons. The Torch & Grit test ensures norm-compliant data on flame and abrasion resistance of housing and barrier materials. But our capabilities extend beyond standard tests.
Custom Solutions for Real-World Scenarios
Leveraging our profound expertise and experience, we develop custom test setups mirroring real-world scenarios. These setups encompass various cell types, sizes, and capacities, ensuring comprehensive material evaluations.
We are committed to support your development processes by providing precise insights into material behavior. Partner with 4a engineering GmbH for meticulous material durability testing and benefit from our experience to create safer and more reliable battery solutions.
multiphysics simulation
multiphysics simulation
Multiphysics simulation enables the simultaneous modeling of interconnected physical phenomena, such as electrical, thermal, and mechanical interactions within battery cells. By integrating these domains, our customers can accurately predict battery behavior under varying conditions, optimizing performance, safety, and longevity
Explore our range of service:
cell abuse testing
Crucial for calibrating material models used in battery simulations. By subjecting battery cells to extreme conditions such as overcharging, short-circuiting, and thermal stress, we gather detailed real-world data. This data is then used to refine the material models, ensuring accurate representation of cell behavior under various abuse scenarios
data evaluation
Focuses on the systematic analysis and interpretation of the test data. By leveraging advanced analytical methods, we extract meaningful insights that help to understand the mechanical, thermal, and electrical responses of battery cells. This evaluation is key in refining the material models, ensuring the simulation models are based on robust, real-world data.
optimization
Involves the fine-tuning of simulation models through automated calibration algorithms. Using state-of-the-art optimization techniques, we adjust model parameters to minimize discrepancies between simulated and real-world data. This iterative process enhances the predictive accuracy of the simulations, ensuring that the models can reliably simulate battery performance and safety characteristics under a wide range of conditions.
multiphysics simulation
Integrates a variety of physical domains, including thermal, mechanical, and electrical phenomena, to create comprehensive models of battery cells. These simulations provide deep insights into the complex interactions within battery cells, allowing for the prediction of performance, degradation, and failure modes under diverse operating conditions. The coupling of multiple physical effects leads to a more accurate and holistic understanding of battery behavior.
validation
Process of verifying the accuracy of simulation models by comparing them to real-world experimental data. Through a rigorous process of cross-checking simulation outputs with observed test results, we ensure that our models accurately predict battery behavior under a variety of conditions. This validation step is crucial for confirming the reliability of the simulations and for ensuring that they can be confidently used in safety-critical applications
digital twin of battery cells
Fully calibrated and validated simulation model creates a digital twin of the battery cell, which is a virtual replica that can be integrated into larger system simulations. This digital twin allows our clients to incorporate highly accurate battery models into applications such as crash simulations, thermal management studies, and performance assessments. By using the digital twin, clients can predict the real-world behavior of battery cells with high confidence, improving design and safety outcomes
In today‘s battery landscape, multiphysics simulation is the key to innovation. At 4a engineering GmbH, we specialize in generating digital twins of battery cells utilizing advanced multi- physics modeling techniques. Merging precise experimental data and sophisticated multi-physics modeling, we create digital twins of battery cells that enable accurate predictions of their behavior. Our holistic modeling framework incorporates mechanical, electromagnetic and thermal properties, capturing intricate interactions at various levels.
benefits of our approach
- rigorous model verification and automated parameter optimization for reliable simulations
- enhanced safety analysis through understanding damage-thermal relationships
- seamlessly integratable, validated digital twins of cells to pack models for thermal propagation predicitions
- mesoscale modeling for detailed component behavior, transferring insights to macro models for pack propagation simulations