What’s the Difference Between Punching and Laser Cutting in Electrode Production?

In the production of lithium-ion battery electrodes, the method used to cut foil materials directly affects the quality, efficiency and cost of manufacturing. Two commonly used processes—mechanical punching and laser cutting—each offer distinct advantages depending on the application.

Punching is a long-established method favored for its high-speed throughput and cost-effectiveness in large-scale production runs involving uniform, simple geometries. However, as electrode designs become more intricate and manufacturers demand higher edge quality and process flexibility, the limitations of punching—such as die wear, required tool changes and potential for material distortion—become more apparent.

Laser cutting, by contrast, is a non-contact process that offers greater precision, cleaner edges and adaptability to various foil geometries and materials. In modern electrode manufacturing, particularly in roll-to-roll applications, laser notching enables the continuous processing of battery foils at high speeds while minimizing particulate contamination—an important consideration for maintaining electrochemical performance. This article looks at the key differences between the two methods.

Laser Cutting for Battery Foil Processing

Sonplas has developed a laser cutting process that enables the efficient and sustainable processing of lithium-ion battery cell foils. This technology can also be applied across various industries, including paper, solar and medical sectors as well as hydrogen applications like H2 MEA. Especially for complex shapes, laser cutting proves to be more cost-effective than traditional mechanical cutting or punching. It delivers higher quality, reduces operating costs and offers greater flexibility. Sonplas collaborates closely with its customers to develop the right solution for them.

“Achieving optimal cut edge quality is a key factor in electrode production,” said Luca Schmerbeck, product manager at Sonplas. The special-purpose machine manufacturer from Straubing designs, builds and delivers customized testing and assembly systems, primarily for the automotive, electronics and aerospace industries. In addition to assembling rotors, inverters and other components for electric vehicles, Sonplas also specializes in battery cell production. “To enhance productivity, we provide solutions that allow our customers to cut battery foils using a laser-based roll-to-roll process, known as notching,” Schmerbeck said. In this process, the edges of the foils are trimmed on-the-fly.

The process operates at extremely high web speeds of up to 4m/sec, ensuring that the electrodes remain free from particle contamination. Additionally, the system is made to handle different geometries without requiring any modifications. The largest electrodes on the market fall within the 700 × 700 mm machining range. “The results are highly accurate, and due to the low heat input in this contactless cutting process, a wide range of materials can be processed—from metal to paper—while maintaining consistently high cutting quality,” Schmerbeck said. “This means we can apply this process to all industries where foil cutting needs to be cost-effective.” In sheet metal processing, lasers have become a core component of many manufacturing processes, offering an alternative to punching.

Laser Cutting or Punching?

Which method is suitable depends on the application. Punching is a long-established method favored for its high-speed throughput and cost-effectiveness in large-scale production runs involving uniform, simple geometries. Punching allows for a fast cycle time for simple cuts. For basic shapes, punching can often complete a cut in a single basic stroke. It is a cold process, which means there is no heat-affected zone (HAZ); this can be useful if there is a concern that even minimal thermal input might affect material structure or downstream performance in sensitive applications.  

That said, as electrode designs become more intricate and manufacturers demand higher edge quality and process flexibility, the limitations of punching—such as die wear, required tool changes and potential for material distortion—become more apparent.

“The laser typically has a clear advantage, particularly in terms of edge and surface quality,” Schmerbeck said. If complex contours or different components need to be processed alternately, laser cutting is typically more efficient, faster and more precise.

The user also has more flexibility when switching products. While a laser can follow various contours and the operator can easily adjust parameters like material thickness, punching requires the right die for each component and material. The die can wear out due to the punched materials, and it will need to be sharpened or sometimes replaced, leading to downtime and material costs.

Depending on operating time, this can make the use of a laser pay for itself quickly. In sheet metal processing, individual parts or small batches can be produced cost-effectively in a single operation without the need to change tools.

Applications Across Industries

Due to its versatility, operators can utilize laser cutting in a range of industries, including fuel cell technology. In the automotive industry, fuel cells are seen as a promising solution for future energy generation. To produce them cost-effectively and with high-quality standards suitable for the mass market, manufacturers can use laser cutting to precisely cut metal sheets as thin as 100 micrometers and then weld them into gas-tight stacks with precision.

“At Sonplas, we can currently process thicknesses ranging from 8 to 300 micrometers,” Schmerbeck said. The process is also suitable for the medical technology sector, such as in the production of filters. This is mainly due to the low heat input during the non-contact processing with the laser beam, which results in distortion-free cutting. The thermal laser process also seals the cut edges when cutting synthetic textiles. “The user benefits from clean and reproducible cut edges, with no need for post-processing,” Schmerbeck said.

“We can envision many more industries as well,” he said, referring to printed electronics, where electronic components, assemblies and applications are produced fully or partially using printing processes. The electronics printed on plastic film can be precisely cut out using a laser.

“There’s a suitable laser for every material on a roll," Schmerbeck said.