Vision solutions for EV battery production (Assembly)

Intelligent vision systems provide the key to higher productivity, greater efficiency and total quality assurance and help manufacturers achieve highest product quality, consistency in the production and minimizing waste.

Machine vision solutions can be used in several steps of the lithium battery production such as battery module assembly, Cell stack assembly; gap filler applications, tightening of modules, cover sealing and cover to tray assembly.


 

Cell stack assembly

A consistent, uninterrupted bead needs to be applied in the right position and the correct width. Achieving this guarantees the optimal joining and therefore the performance of the battery. Tight production tolerances on mixed surface characteristics like shiny, matt and dark surface finish require precise 3D robot guidance for the gap filler application, as the overall process quality depends on accuracy and reliability of the vision technology.

Process efficiency and high quality

Fast image processing algorithms during computing increase the speed and accuracy of the bead application process. The MONOxD Software calculates the 3D coordinate transformation and sends the offset to the robot controller to optimize the tool path. 

With a lean product design for highest flexibility, MONO3D is adaptable to all production scenarios as gripper-mounted, stationary or robot-mounted solution in a scalable set-up with a large field of view depending on working distance.

Select production step

Cell component inspectionCell inspectionCell stack assembly ⇒ Module assembly ⇒ Battery tray assembly ⇒ Thermal managementAssembly of modules ⇒ Assembly of electrical components ⇒ Fire protection ⇒ Cover sealingCover to tray assembly


 

Thermal management - control of gap filler application

Optimal thermal management is crucial for every battery. A thermal compound material is needed to manage the battery heat, but applying the correct material volume is challenging. To meet the high safety requirements and maximum performance in battery manufacturing, the thermal compound material needs to be applied continuously, in the right position, the right width and the right height. Balanced and sufficient material distribution for optimal conductivity and heat dissipation avoids defects of the battery.

Process efficiency and quality inspection in three dimensions

Fast image processing algorithms during computing increase the speed and accuracy of the bead application process. The MONOxD Software calculates the 3D coordinate transformation and sends the offset to the robot controller to optimize the tool path. RTVision.3d is the ideal solution for the inspection of bead quality as it not only can measure the width, position, and continuity of the bead application but also its height. 

The 100% 3D inline solution allows measurement of the actually applied material volume that ensures an optimal conductivity and heat dissipation. The included automatic bead repair function allows to automatically repair an interrupted bead if detected by the system. This avoids manual rework or even scrap of the part.
The system provides real-time feedback on the user guidance, if an error has been detected and where to increase quality and avoid errors. The complete process is fully transparent and documented in the software.

Select production step

Cell component inspectionCell inspectionCell stack assembly ⇒ Module assembly ⇒ Battery tray assembly ⇒ Thermal management Assembly of modules ⇒ Assembly of electrical components ⇒ Fire protection ⇒ Cover sealingCover to tray assembly


 

Assembly of modules

After dispensing the compound thermal material, the module needs to be mounted and tightened to the battery tray. The close contact between modules and gap filler is crucial for thermal transfer, but consistent tightening quality with limited cycle time is challenging.

Safe assembly processes based on point-cloud technology

To avoid serious production quality issues and achieve short cycle times, the PowerPICK3D sensor ensures foreign part free assembly situation with its ultra-fast quality inspection and result provision. After acquiring the point cloud, the embedded processing unit compares the point cloud generated in production environment and calculates deviations from the CAD-file based on tolerances defined.

Following the quality inspection, a multispindle with MONO3D robot guidance allows a perfect tightening process. Fast image processing algorithms during computing increase the speed and accuracy of the tightening process. The MONOxD Software calculates the 3D coordinate transformation and sends the offset to the robot controller to optimize the tool path.

Select production step

Cell component inspectionCell inspectionCell stack assembly ⇒ Module assembly ⇒ Battery tray assembly ⇒ Thermal managementAssembly of modules ⇒ Assembly of electrical components ⇒ Fire protection ⇒ Cover sealingCover to tray assembly


 

Cover sealing application with quality monitoring

Once all modules are tightly fixed and the battery management system is installed, the tray must be sealed. Humidity dramatically decreases battery performance and can damage the high-voltage system and delicate cells. Additionally, the battery emits gases which can be hazardous.

To keep humidity out and prevent gas leakage, the battery tray must be sealed before the cover is mounted completely both from inside and outside. This requires a 100% tight cover sealing application with a continuous bead and precise bead beginning and end.

Therefore, a reliable bead inspection is crucial for performance and lifetime of the battery.

Fully integrated 100% visual inspection of position, width and continuity of the bead

With RTVision.3d, it is possible not only to measure the width, position, and continuity of the bead application but also its height. This allows measurement of the actually applied material volume. The included automatic bead repair function allows to automatically repair an interrupted bead if detected by the system. This avoids manual rework or even scrap of the part. Demanding material requires optimal temperature management to guarantee adhesion and serviceability of the battery. In many cases, hot butyl is used because it can be easily removed and improves serviceability. With fully heated systems, we ensure accurate tempering for hot materials.

Select production step

Cell component inspectionCell inspectionCell stack assembly ⇒ Module assembly ⇒ Battery tray assembly ⇒ Thermal managementAssembly of modules ⇒ Assembly of electrical components ⇒ Fire protection ⇒ Cover sealingCover to tray assembly


 

Cover to tray assembly

The final step of battery assembly is the mounting of the cover onto the battery tray. When joining a battery cover to its tray, more than 100 fasteners can be needed. This requires a fast application to achieve a short cycle time.

Precise positioning of the joining tool is crucial for the assembly process step to deliver the highest quality standards. MONO 3D performs pick-and-place of battery covers precisely and enables fast and reliable robot guidance which is the key driver for high-volume production. Fast image processing algorithms during computing increase the speed and accuracy of the tightening process. The MONOxD Software calculates the 3D coordinate transformation and sends the offset to the robot controller to optimize the tool path.

Highly accurate and traceable in-line measurement technology

Every attachment feature on the tray must have proper alignment to each other and the cover. Missing or out of tolerance features cause assembly and safety issues. Also, taking battery assemblies out of the production line for offline sampling is costly and does not provide enough information to guarantee quality standards are met.

100% inline measurement of all battery trays and covers with Helix Evo sensor with AccuSite technology immediately identifies faulty assemblies without the necessity of transporting them in and out of the manufacturing line. Advanced sensors and algorithms accurately scan and report variation from nominal including threaded studs, rivets, surfaces, and more.

Select production step

Cell component inspectionCell inspectionCell stack assembly ⇒ Module assembly ⇒ Battery tray assembly ⇒ Thermal managementAssembly of modules ⇒ Assembly of electrical components ⇒ Fire protection ⇒ Cover sealingCover to tray assembly


 

 

Contact me if you have any questions. I will be happy to advise you.

ISRA VISION GmbH

Andreas Hafner
Smart Factory Automation
Global Key Account Manager

Phone:
+49 172 2980-925
E-Mail:
ahafner@isravision.remove-this.com

Achieve the highest product quality with vision solutions for EV battery production.