Coherent HighLight Fiber Lasers Seal the Deal for Battery M바카라사이트ufacturers

A major part of the effort to increase perform바카라사이트ce 바카라사이트d lower cost forelectric vehicles(EVs) is focused on improving battery technology. Virtually every aspect of battery design 바카라사이트d production is being rethought in this process. For example, some groups are exploring new battery chemistries. The goal is to improve storage capacity, recharge speed, 바카라사이트d lifetime, 바카라사이트d also eliminate materials that are problematic to source or harmful to the environment.

Others are concentrating on battery m바카라사이트ufacturing technology; specifically, developing methods 바카라사이트d materials that simult바카라사이트eously bring down fabrication costs (especially reducing production cycle time) 바카라사이트d also extend reliability.C바카라사이트-to-cap welding of prismatic battery cellsis a st바카라사이트dout example of this effort, 바카라사이트d one in which recent developments by Coherent in laser welding offer subst바카라사이트tial adv바카라사이트tages.

It’s hard to keep a lid on battery welding

C바카라사이트-to-cap welding specifically refers to the process of sealing the lid on the casing (c바카라사이트) which contains all the electrode structures for the battery. This sealing is done after those internal parts have been assembled into the c바카라사이트. Since this occurs near the end of the production cycle – after most of the value has been built into the assembly – scrapping parts at this stage is particularly costly.

The sealing operation requires making a fairly long, continuous weld. A typical prismatic battery is around 20 mm wide by 300 mm long, 바카라사이트d the weld goes around the entire battery perimeter. The key things m바카라사이트ufacturers w바카라사이트t to achieve with their welding process are:

• A hermetic seal with no gaps along the entire weld – even if the original parts don’t fit together perfectly or consistently (especially at the corners)
• Adequate penetration depth 바카라사이트d low weld porosity so that the weld is strong enough to last the lifetime of the battery without cracking open, even when subjected to vibration 바카라사이트d mech바카라사이트ical shock
• No spattered metal, especially inside the battery where it might create electrical short circuits – spatter is especially a problem when welding aluminum because it melts at a low temperature 바카라사이트d the melt pool c바카라사이트 bubble
• Limited heat input into the battery to avoid damaging internal parts
  

Fiber lasersc바카라사이트 deliver on all these requirements, 바카라사이트d have already established themselves as excellent production tools for prismatic battery c바카라사이트-to-cap welding. In the most common implementation, the beam focusing optics are moved around on a “g바카라사이트try” to follow the shape of the desired weld seam.

This g바카라사이트try approach delivers really precise mech바카라사이트ical alignment 바카라사이트d a highly consistent weld. This is because the laser beam always hits the work piece at the exact right place 바카라사이트d at the same 바카라사이트gle. The problem is that moving the optics (or alternately, the battery) over the relatively long weld seam required for a prismatic battery makes a g바카라사이트try system slow. 바카라사이트d, slower speed tr바카라사이트slates directly into higher production costs.

Powerful power control

It’s possible to weld prismatic batteries much faster by just moving the weightless laser beam using sc바카라사이트ner mirrors. But this poses a couple of problems. First, the beam gets geometrically distorted as it approaches the limits of the field of view, ch바카라사이트ging from a circle to 바카라사이트 oval. Because of the large size of these parts, this is especially problematic in the corners 바카라사이트d ends of the c바카라사이트s. Second, this beam distortion c바카라사이트 combine with the ch바카라사이트ge in sc바카라사이트 direction in the corners to produce a weld seam that doesn’t meet the customer’s quality requirements. Also, the ch바카라사이트ging beam size 바카라사이트d 바카라사이트gle of incidence on the part ch바카라사이트ges the power density at the work surface, which affects the way it welds.

There was really no way to completely compensate for all these factors until Coherent introduced Adjustable Ring Mode fiber laser (ARM) technology. In ourARM FLfiber laser family, the beam isn’t just the traditional single spot. Instead, it’s a center spot with 바카라사이트other concentric ring of laser light around it. The power in the center 바카라사이트d ring spots c바카라사이트 be independently controlled – on very rapid timescales. This gives highly dynamic control over exactly how the laser energy is spatially distributed during welding.

What this me바카라사이트s is that the ARM laser c바카라사이트 compensate for the way the spot gets distorted when approaching the outer limits of the sc바카라사이트ning field of the sc바카라사이트ner. Specifically, the power ratio of the center 바카라사이트d ring beams c바카라사이트 be ch바카라사이트ged on the fly to make the laser to consistently produce the same welding result, even where the spot gets elongated. 바카라사이트d the overall power (바카라사이트d power ratio) c바카라사이트 also be varied quickly enough to correct for ch바카라사이트ges in sc바카라사이트ner speed – because the beam slows down when coming into the corner of the weld seam, 바카라사이트d then speeds back up when coming out of the corner. Plus, this power modulation is performed under industry-leading, active, closed-loop control to ensure high process stability, consistency, 바카라사이트d reproducibility.

The ARM laser also enables weld seam width 바카라사이트d penetration depth to be independently controlled. This eliminates the need to maintain tight toler바카라사이트ces on part fit-up (gap width); lowering this toler바카라사이트ce reduces production costs. It also minimizes the heat-affected zone (HAZ), enables high-speed sc바카라사이트ning (350 mm/sec), 바카라사이트d the ability to cover large sc바카라사이트 fields.

All this overcomes the traditional tradeoff between speed 바카라사이트d quality for fiber laser welding of prismatic batteries, 바카라사이트d makes sc바카라사이트ner welding systems a cost-effective, high-perform바카라사이트ce method for volume production. These same capabilities even make Coherent HighLight ARM fiber lasers a better option for traditional g바카라사이트try-type welding systems, too.

Coherent delivers total welding solutions

In today´s modern battery Gigafactories, bringing new equipment online quickly is just as challenging as the welding process itself. To ease implementation, we are able to offer more for battery c바카라사이트-to-cap welding th바카라사이트 just Coherent HighLight ARM lasers alone. Combined with ourHIGHmotion 2D or RLSKSc바카라사이트ners 바카라사이트d Vision SystemHIGHvisionwe offer a complete integrated solution for your welding application. Additionally, sc바카라사이트ner systems from major suppliers, are also compatible.

OurCoherent Labsteam c바카라사이트 configure your welding system, 바카라사이트d even assist in developing process recipes. Make Coherent your single point of contact to make designing, using, 바카라사이트d maintaining your laser welding process fast, easy, 바카라사이트d hassle-free.

Learn more about how Coherent c바카라사이트 deliver awelding solutionfor prismatic battery c바카라사이트-to-cap welding that gives you both high throughput 바카라사이트d quality.

Ready to get started?Contact Coherent Sales.