Battery cases are a core component of new energy vehicles (NEVs). They must balance lightweight design, structural integrity and safety, while ensuring compliance with strict sealing and durability requirements. One of the critical factors in battery case performance is the flatness of the mounting surfaces, which directly impacts sealing reliability and long-term safety.

OTS’s technology partner, PMT Technologies, provided a precision metrology solution to address these challenges and ensure manufacturing quality in the production of battery shells.

Objective:

To accurately measure and validate the flatness of the mounting surfaces of the upper and lower shells of the battery box, ensuring reliable sealing performance and compliance with IP67 water-resistance standards.

Challenges in the Project

• Flatness & Sealing Reliability: the silicon rubber sealing ring must maintain a precise level of compression. Any deviation in the flatness of the shell mounting surfaces can cause over-compression or under-compression, leading to seal failure and safety risks.
• Limitations of Traditional Tools: conventional methods such as feeler gauges and dial gauges lacked the required efficiency and precision. These manual techniques made it difficult to guarantee repeatability and consistent accuracy in a production environment.

Solution

PMT Alpha Arm was deployed for advanced 3D measurement and analysis:

• High-Precision Point Measurement: captured multiple point positions across the battery shell surfaces with high accuracy.
• Digital Data Processing: converted measurement data into a reference model for direct comparison with theoretical design values.
• Real-Time Flatness Validation: enabled engineers to easily visualize dimensional deviations, ensuring precise control over flatness standards.

Results

• Increased Accuracy: achieved reliable detection of flatness deviations that traditional tools could not identify.
• Improved Efficiency: reduced inspection time and eliminated repetitive manual checks.
• Enhanced Quality Control: guaranteed proper compression of the sealing ring, maintaining IP67 water resistance and preventing failure risks.
• Support for NEV Innovation: Ensured that the structural and sealing integrity of battery cases meets the demanding requirements of the new energy vehicle industry.

Conclusion

By integrating the PMT Alpha Arm into the battery case production process, a scalable, efficient and accurate measurement solution was delivered. This enabled manufacturers to ensure the safety, performance, and reliability of new energy vehicle batteries, strengthening their position in a highly competitive market.