Real-time laser power and beam profile monitoring for an EV battery manufacturer

Case study

Application: Laser battery welding

Measurement type: Real-time laser power measurement, beam profiling

Customer goals

An EV battery manufacturer is committed to achieving its sustainability goals. To support their efforts, they employ energy management systems at each site to track and reduce energy consumption.

The adoption of cutting-edge technologies, including laser power and beam profile monitoring systems, plays a crucial role in optimizing energy usage and enhancing process efficiency. By minimizing waste and ensuring precise welding, the customer maximizes ROI and contributes to their sustainability objectives.

It can take over 100 individual welds to manufacture an EV battery. Consequentially, if one weld is faulty because the laser power is incorrect, there is a significant loss in time, energy, and environmental waste, even if the weld fault is detected. Monitoring their lasers in real-time results in minimal losses.

It’s also a hot topic that cars could combust because of a mis-soldered battery. For example, it happened to other major manufacturers: a shipping vessel loaded with thousands of cars was set aflame. Ensuring quality laser welds improves not only human safety but also improves the overall perception of EVs.

Challenges

The laser welding process of the customer involves very short laser pulses. To ensure the utmost precision and stability, they need to monitor the energy pulse by pulse. This implies that the laser output has to be analyzed not only in terms of average power stability but also at the scale of each welding pulse.

This level of detailed monitoring is a significant improvement over traditional spot checks, providing the customer with a comprehensive view of the laser's performance throughout the welding process.

The customer works with a 300-watt, 1064 nm pulsed laser source that operates at 1 Hz and each weld takes 10ms and J level of energy. RS-232 connectivity is a requirement from the customer.  

We also had to take into account the customer’s unique system size. For example, this EV battery manufacturer needed a longer than standard cable between the laser power detector and display unit / PC interface. One can’t simply use an extension cable when doing high-accuracy laser power measurement as this would affect the measurements.

Gentec-EO’s solutions

Our meticulous approach led us to design a 2-part solution. The first part involves integrated laser power measurement and the second involves beam profile monitoring.

Part 1 - Enhanced laser power monitoring

The customer integrated thermopile-based laser power meters into their laser system, enabling them to measure the full power of the laser at different positions inside the system, particularly during beam shaping. With these measurements, they can retrospectively adjust the laser power output from the 1064nm laser source at each step. This dynamic control allows them to optimize the welding process and minimize any fluctuations or deviations in laser power, ensuring consistent and reliable welding.

In this specific situation, the designed solution is to make a first power measurement with a UP55N-300F-H12-IDR, then make some beam shaping, and after 2 more lenses make a second power monitoring with a UP19K-110F-H9-IDR-D0. The UP series was perfectly tailored to their systems thanks to its compact and high-speed thermopile-based design. 

UP55N-300F-H12-IDR

UP19K-110F-H9-IDR-D0

The customer chose to leverage the power of Gentec-EO’s INTEGRA solution for both of these laser power measurement instruments. INTEGRA is available as an option for many of our product series and allows the customer to read their measurement data directly on their PC or acquisition system thanks to an RS-232 or USB connection.  

Part 2 - Precise laser beam profile monitoring

The BEAMAGE-4M-FOCUS camera serves as the final monitoring point for the customer's laser system. Before the beam delivery on target, they take a sample of the laser to measure mW-level of power from their 5.5 mm beam.

BEAMAGE-4M-FOCUS

By examining the laser profile and position, they can anticipate and control the beam focus at the working point. This proactive approach helps prevent any shifting issues caused by thermal lensing, ensuring the laser beam remains focused accurately during welding. The real-time nature of this monitoring allows for immediate adjustments, resulting in higher welding quality and improved process efficiency.

Results

By working with thermopile-based laser power meters and the BEAMAGE-4M-FOCUS camera, the customer has achieved real-time control over its laser welding process, ensuring high-quality welding and enhancing its return on investment.

The in-line stability monitoring ensures the highest quality output and aligns with their sustainability goals. With a focus on energy efficiency and process optimization, the customer continues to lead the industry in EV battery manufacturing, setting new standards for performance and sustainability.

We are also working closely with the customer to address other laser beam measurement challenges as they occur.

Through adaptability, flexibility, and foresight, we have forged a strong relationship that continues to thrive, making a significant impact in the EV battery manufacturing sector.

Let us help you achieve results

Gentec Electro-Optics specializes in laser beam measurement and analysis. With an outstanding 50-year track record of innovation, developing and providing state-of-the-art technologies to the laser market, Gentec-EO has become The Expert of the laser beam measurement field.

Gentec-EO offers the broadest range of off-the-shelf and custom laser beam measurement solutions. Challenge us with your laser specs and system requirements and we'll come up with the measurement solution that meets your needs.

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