Using Vision Systems to Solve EV Battery Inspection Challenges

Flexible and metallic, pouch EV batteries are susceptible to specular glare and wrinkles, making defect detection difficult.

Prismatic battery cells require a lot of welding. Separating acceptable weld anomalies from defective weld seams can be challenging for a vision system.

For cylindrical battery cells, manufacturers etch lot codes, material origin, and other important information directly on the battery to make recalls possible, isolate issues in production, and comply with regulatory requirements. Ensuring the accuracy and correctness of printed codes can be problematic due to the print orientation often used.

Codes can be printed anywhere on the sides of the battery. The shape of the batteries, being round or metallic, can cause deformed or distorted coding, making code reading and verifications challenging. Machine vision can help address these EV battery inspection challenges.

Vision systems for automotive manufacturing from KEYENCE can be used to address issues with specular glare and wrinkles in pouch-style battery inspections. We have solutions with AI detection capabilities in addition to rule-based detection programming.

Rule-based programming is limited to predefined rules, meaning defects outside of programmed variables and iterations of defects can go undetected. AI-powered detection technology, on the other hand, analyzes thousands of labeled images to learn what “good” and “bad” batteries look like and continuously uses data to improve system accuracy.

Equipped with powerful high-resolution cameras and an advanced illumination unit, our machine vision solution can detect flaws in prismatic battery weld seams and inconsistencies in cylindrical battery coding information.

Regardless of the EV battery type, cracks in the battery cells or modules, electrode misalignment, corrosion, terminal damage, and dimensional inaccuracies are common sets of challenges that can affect the safety and reliability of EV batteries.

Cracks can expose the internal components of an EV battery to surrounding spaces, increasing the risk of thermal runaway. This situation can lead to fire or explosion.

Improper placement of electrodes can lead to uneven current distribution. It can also increase the internal resistance of the battery, causing decreased power output and slower charging times.

In pouch cells, warped or bent cells can lead to battery performance and safety issues. During pouch cell production runs, accurate inspection is especially required as these battery types are more prone to dimensional inaccuracies due to their flexible design. Making sure even subtle defects are accurately detected depends on the capability of the vision system being used.

KEYENCE EV battery defect inspection solutions use powerful cameras to capture high-definition images and feed captured data to a powerful image processing unit that uses artificial intelligence to identify and classify defects.

To stand out in a highly competitive market, manufacturers need to reduce cycle times and scale up production. One way to stay relevant is to get products into the market fast. Speed, however, must be achieved with production efficiency and regulation compliance in mind.

For example, there is no point in achieving 200 production parts per minute when there are structural issues like loose terminals, warped cells, and incorrect connections passing on to the next stage of production undetected. A high throughput without quality assurance is a quick way to upset any client base and become irrelevant in the market.

The right vision solution should be able to cover a greater field of view, perform simultaneous image capture, and do a quick analysis of capture data to keep up with the demands of today’s fast-moving battery production plants.

KEYENCE vision systems help manufacturers in speed and efficiency efforts without sacrificing quality. Our LumiTrax™️ technology, for instance, combines intelligent directional lighting with high-speed cameras and advanced image processing algorithms to deliver reliable rapid EV battery inspection results.

The rise in the demand for safer, more efficient, and reliable EV batteries means more stringent testing and compliance requirements.

First, manufactured batteries are tested for performance to ensure they meet charging efficiency, voltage stability, energy capacity, and cycle life requirements. Also, regulatory compliance demands that EV batteries tick production boxes for energy efficiency, safety, and energy emissions.

Interoperability testing is another standard covering the compatibility of coupled battery systems with charging stations. Moreover, environmental impact standards ask that production processes and EV batteries adhere to recycling guidelines and responsible handling of hazardous materials.

EV battery inspection assists in achieving compliance with these many standards by helping engineers check for defects that can affect product integrity at every production stage.