The rise of electromobility is unstoppable. This refers not only to passenger cars, but also to fully electric buses and other commercial vehicles. At the heart of all promising mobility concepts are the traction batteries used, which provide the necessary power to ensure that drivers and passengers reach their destinations safely. Safety here refers to two aspects: on the one hand, the range (which can be ensured via a sufficient charging station infrastructure as well as the charging capacity of batteries) and, on the other hand, the intrinsic safety of the batteries. Quote ADAC: “Intrinsically safe means that the current flow of the battery is stopped if a defect occurs in the system.” In plain language: If, for example, an accident occurs, the battery is immediately disconnected automatically from the other high-voltage components and the high-voltage cables so that there is no longer any voltage present.
However, this text does not address design aspects related to range nor intrinsic safety in the event of accidents or other unexpected events. The issue here is the basic battery quality. What is the best way to ensure that batteries installed in vehicles are not defective, are in working condition, and provide the targeted performance?
Efficient battery production with comprehensive quality assurance
As with other manufacturing processes, one thing is clear: If quality assurance only takes place at the end of production (EOL), battery manufacturers are giving away a lot of potential for minimizing labour and costs.
Efficient battery production with comprehensive quality assurance requires distributed and decentralised concepts that are integrated into the production process at the crucial points. However, it is also important to implement an end-to-end test strategy that optimally maps the overall process and the product and generates a detailed quality report at the end of the value chain.
The system solution by ProNES automation GmbH, which was registered last year under the brand name batterieinspektor, offers the possibility to carry out quality assurance in the required staggered form. The test parameters can be integrated according to the requirements for the respective process status and depending on the battery type:
- Inspection of the individual battery cell as incoming goods inspection
- Functional test and balancing of the mounted battery modules
- Function test and safety tests on the BMU
- Overall test of the final assembled battery pack and SoC alignment
The system solution with a modular structure, which has emerged from use in production, ensures simple integration into the customer-specific production environments and allows the selected solution to be adapted to the specific requirements in order to scale the solution in line with demand in the course of further technical innovations in battery technology. The generally defined requirements of the automotive industry, such as compliance with LV123, are fully taken into account and integrated.
Structure of batterieinspektor
The battery inspector has a modular design. It consists of software and hardware modules. The modules defined in the basic system describe the basic software and hardware foundation for a testing facility, which provides all the prerequisites for configuring a demand-oriented QA solution. In addition to the necessary measurement technology, the high-voltage components and all other required power supplies, this includes interfaces that are necessary for the further processing of the acquired data as well as indispensable database and reporting functions.
This basic system can then be modularly adapted to the respective requirement profile. Here are just three modules that have proven to be central in our daily practice:
The climate module can be used to actively temper a battery pack with a liquid cooling circuit (water-glycol mixture). The module offers all functions for setting temperature specifications with controlled flow and pressure. The temperature range for the batterieinspektor is from -10 °C to +100 °C. A dedicated real-time controller monitors the required process technology. The controller communicates with the higher-level MCT module to set the desired conditions from the test sequences. Before the coolant is introduced, a pressure test is performed at the connections. After the test routines have been completed, the coolant is drained again, and the entire circuit of the heat exchanger system is blown free using compressed air. Monitored activated carbon filters in the air conditioning system ensure the required cleanliness of the cooling medium.
This module serves to automatically check the tightness of the heat exchanger unit and the connection pipes. The module works with two different methods.
- Pressure and flow measurement at the connection pipes
- Differential pressure measurement of the heat exchanger unit
In differential pressure measurement, the module subjects the DUT to a defined test pressure. After a settling phase, the module measures the pressure loss.
Since the measurement is integrated on two sides, pressures up to 20 bar can be realized, but also very small pressure ranges and leak rates.
Traceability is a decisive criterion for smart factories for battery production. If problems occur with the finished battery packs despite all QA measures, given the appropriate configuration, the production chain can be reconstructed step by step and component by component. This offers the opportunity to target problems precisely at the critical points. At the same time, the collected data allows for better exploiting potentials for process optimisation. Since a clear allocation of data to the various components is possible, manufacturers can better plan and control both internal production steps and operational processes in the surrounding area in real time. Finally, the batterieinspektor by ProNES also ensures that the state of delivery (SoC) is established for the batteries.
The Bottom Line
Im erprobten Gesamtpaket sorgt eine vollumfängliche, modulare Systemlösung zur Batterieprüfung dafür, dass sich die Batteriefertigung in der Smart Factory umsetzen und optimal an die Kundenbedürfnisse anpassen lässt. Dies erlaubt es allen Batterieherstellern, Batteriesysteme zu liefern, die allen Qualitätsanforderungen gerecht werden.
In the proven overall package, a fully comprehensive, modular system solution for battery testing ensures that battery production can be implemented in the Smart Factory and optimally adapted to customer requirements. Thus, battery manufacturers can supply batteries that meet all quality requirements.
You can find more information about the batterieinspektor under the following link: