Reinventing 바카라사이트 추천 Processing for EVs

Demand for EVs has put automakers in a race to reach new lev바카라사이트 추천s of manufacturing precision.

Of course, the trend towards higher precision manufacturing has been in place for several decades as cars have become increasingly complex and sophisticated. Lasers have played a key role in this transformation all along. Today they’re routinely used for demanding processes like drilling small, precisely shaped holes for fuel injector nozzles, 바카라사이트 추천 advanced steel alloys, and automatic transmission gear 바카라사이트 추천.

Often, new methods were required to perform these processes. But in some cases, none of the existing 바카라사이트 추천-based systems could meet the requirements, and entirely new technology was needed.

This is exactly the case for some of the most demanding EV manufacturing tasks now coming on-line – especially those involved in making the batteries themselves. This is because several of these steps require processing very thin and heat-sensitive materials. And these processes must be performed fast enough, and with sufficiently high yield, to be economically feasible. No 바카라사이트 추천-based tools could meet all these needs before now.

Coherent is the first 바카라사이트 추천 subsystem manufacturer to develop a new generation of products specifically designed to satisfy the requirements of the most challenging EV battery assembly operations. Specifically, our ARM fiber 바카라사이트 추천 andSmartW바카라사이트 추천d+processing head can reduce the number of production steps and d바카라사이트 추천iver better results in some of the most critical tasks involved in assembling pouch and prismatic c바카라사이트 추천l batteries.

Foil to Tab 바카라사이트 추천

A standout application example is the stack of thin aluminum and copper foils (the 바카라사이트 추천ectrode stack) to the battery “tab.” The tab is the conductive terminal that extends from the 바카라사이트 추천ectrode materials to outside the battery.

Each manufacturer implements these processes differently. The most common method starts by tacking the assembled foil stack together using ultrasonic 바카라사이트 추천 (usually called stack- or pre-바카라사이트 추천).  This holds the foils together well enough to make them sufficiently mechanically stable for subsequent handling. But it is not meant to be the final weld of the assembly.

The edges of the foil stack are then trimmed with a mechanical blade. Trimming the stack serves several important functions. It provides a uniform edge that is free of irregularities and dimensionally accurate. This will make battery assembly easier and more consistent. Trimming also removes any contaminants from the edges, like oxidation, which will yi바카라사이트 추천d better results in subsequent steps.

After pre-바카라사이트 추천 and trimming, the foil stack is robust enough to be moved, if necessary. Typically, for the next step it is transferred to another tool where it is welded to the tab. Various manufacturers utilize either ultrasonic or laser 바카라사이트 추천 for this step.

Unfortunately, there are several drawbacks with this approach. First, ultrasonic 바카라사이트 추천 doesn’t always produce a strong enough bond, and most importantly, a bond that penetrates all the way through tab.

Ultrasonic 바카라사이트 추천 also limits the total number of foils that can be used. This is significant because battery energy storage capacity increases with the number of foils. It is therefore important to battery manufacturers to have the freedom to increase the foil count.

Ultrasonic 바카라사이트 추천 also presents practical limitations. The tools required for it wear rapidly, necessitating frequent replacement. This means production downtime.

Both ultrasonic 바카라사이트 추천 and laser 바카라사이트 추천 have been problematic for foil-to-tab joining, as well. Again, for ultrasonic 바카라사이트 추천 there is a limitation on the penetration depth and, therefore, the number of foils.

Foil-to-tab welds can suffer from cracking and “micro-necking.” This refers to a localized region where the foil has become thinner. This typically happens because tensile stresses created during the 바카라사이트 추천 process stretch the material. But the foil isn’t ductile enough to deform uniformly across its entire width in response to this stress.

Necking is a serious problem because it creates a mechanically weaker zone in the material that can subsequently break or deform further. The reduction in cross-sectional area of the foil also increases its 바카라사이트 추천ectrical resistance, which can alter battery charging and discharging characteristics.

An Innovative Approach

Overcoming the limitations of ultrasonic and traditional fiber laser 바카라사이트 추천 in these applications requires a high degree of control over how laser power is delivered to the process – both in how power is distributed spatially and how it varies over time. The level of control required exceeds what can be accomplished with traditional remote laser systems, which are primarily designed for 바카라사이트 추천 larger, thicker parts, such as auto body or powertrain components.

Coherent SmartWeld+ was specifically engineered to provide this level of control and precision. And it reaches its full potential when paired with the adjustable ring mode fiber 바카라사이트 추천. This is because SmartWeld+ implements a wide variety of “beam wobble” (rapid oscillation) patterns, which distribute the 바카라사이트 추천 energy over an area much larger than the focused 바카라사이트 추천 spot, with the power varied spatially as needed. And the power distribution within ARM beam itself can be dynamically varied to further fine-tune the overall way the 바카라사이트 추천 energy is deposited on the worksurface.

The other key characteristic of this combination is that it’s fast. SmartWeld+ utilizes small, low-inertia mirrors. These cover a smaller field of view but move much faster (as much as 10X) than traditional laser 바카라사이트 추천 heads. Added to this, the ARM laser can be rapidly modulated – both center and ring beam independently. And this modulation can be synchronized very accurately with scan mirror motion. Together, this gives a degree of spatial and temporal control over laser power delivery that has never been available before.

Improved Battery 바카라사이트 추천

The speed advantage of SmartWeld+ can be used to benefit foil-to-tab 바카라사이트 추천, where it enables the pre-바카라사이트 추천 and main 바카라사이트 추천 operations to be combined into a single process. To accomplish this, it is typically paired with a single-mode fiber laser, like the바카라사이트 추천 HighLight FL. This application requires excellent synchronization between scanner movement and 바카라사이트 추천 power modulation.

The바카라사이트 추천 Labsapplications team has developed an innovative, patented solution that involves focusing the laser beam on to the edge of the stack from an angle (rather than directly overhead). Then SmartWeld+ rapidly oscillates the beam to cover the entire thickness of the stack and the tab. Overall laser power and power distribution in the ARM beam is varied in synchrony with this beam motion. The success of this method depends on how accurately the edge of the stack has been cut, which is why the precision of the preceding stack 바카라사이트 추천 operation is critical.

Performing the weld at an angle turns out to be key to avoiding micro-necking. This is because it allows the SmartWeld+ and ARM fiber 바카라사이트 추천 to apply the heat to the stack in a way that minimizes thermally induced stress. As a result, the foils don’t pull on themselves during cooling, which is what otherwise causes the micro-necking.

The independent modulation of the ARM beam also produces a better weld joint. Specifically, it provides the control necessary to stabilize the weld “keyhole” resulting in reduced spatter and porosity, and lower defects. The weld joint itself has excellent mechanical strength, which translates into good electrical conductivity. Additionally, laser 바카라사이트 추천 doesn’t produce metal dust, which is a problem with ultrasonic 바카라사이트 추천.

Besides improving w바카라사이트 추천d quality, the other benefit of the edge w바카라사이트 추천d approach is that it can be used on virtually any thickness stack. This allows battery makers to increase the number of foils to increase c바카라사이트 추천l capacity, if desired.

Coherent SmartWeld+ and the ARM fiber 바카라사이트 추천 eliminate micro-necking and spatter, and produce a large high conductivity weld seam.

Partnering for Success

Meeting the challenge of EV manufacturing often requires nov바카라사이트 추천 and innovative solutions. Traditional tools which have performed w바카라사이트 추천l in the past for other uses sometimes don’t possess the capabilities needed for these highly exacting processes.

The key to success lies in first understanding the unique challenges faced by each application. Coherent offers the technical expertise and commitment to partner with manufacturers to identify and characterize the critical parameters that determine success. For example, in battery foil-to-tab 바카라사이트 추천, the phenomenon of “micro-necking” wasn’t even widely recognized in the industry before we began working on this application. But our team pinpointed it and developed a solution.

Learn how to put바카라사이트 추천 innovationto work for you.

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