A Path to Reduced Costs Without Sacrificing Performance

In Battery Packs, “Close Enough” is Not an Option...

With consumer safety, delayed EV adoption, and costly product redesigns on the line, ensuring optimal product performance is paramount. Equally important, though, is keeping your manufacturing costs in check. 

Balancing costs with performance can sometimes feel like a push and pull – giving up one for the other. But by leveraging some actionable design for manufacturability and assembly (DFMA) principles into your development/engineering phase, it doesn’t have to be such a give-and-take. 

Today, we’ll be highlighting some key strategies to help reduce waste and manufacturing costs without sacrificing performance when designing your next die-cut EV battery or energy storage component. We’ll be covering:

• Designing for maximum yield
• Avoiding over-engineering and over-specifying
• Material property considerations
• Prioritizing functional tolerances

Let's take a closer look...

Designing For Maximum Yield

Perhaps the most impactful yet often overlooked aspect of waste and cost reduction is optimizing material yield. Material yield is essentially how much bang for your buck you get out of a roll of material – it's the percentage of raw material that is converted into usable die-cut parts. High yield means less material is wasted as scrap, directly leading to lower material costs and more efficient production.

So, what does design for maximum yield look like in practice?

Optimized nesting

Nesting is really the heart of maximizing material yield. Nesting refers to the way each individual part is laid out on the raw material before it’s cut. The goal is to determine the best orientation and placement of each part on the roll to yield as many parts as possible. This is entirely dependent on the shape of your part, and may require interlocking shapes, staggered patterns, or rotated parts.

If you think with your stomach (like me), think of it like making cookies. Once you’ve rolled the dough out, you obviously want to maximize your cookie output. So, you find the best orientation to stamp your cookie-cutter to fit as many cookie cut-outs in the roll of dough as possible, improving your cookie-to-dough ratio. Viola! You’ve just implemented a much tastier version of DFMA principles and part nesting strategies! 

Avoid Over-Engineering/Over-Specifying

Over-engineering and over-specifying can introduce unnecessary challenges to the die-cutting process — driving up costs and decreasing production efficiency. It’s important to work with a converting partner during the development phase to determine what design factors are truly critical to the functionality of your component.

Over-Engineering

What looks good in concept doesn’t always hold up when it’s time to put it into production. Unnecessary layers, holes, cut-outs, and other design features can make the die-cutting process much more challenging, adding unnecessary risk to each step of production.

For example, in place of a punched-out hole, a simple slit may work, helping reduce both material waste and slugs (small pieces of material waste that need to be ejected from cut-outs). 

Over-Specifying

While it can still feel a bit like the wild west in terms of battery materials, it’s important to select materials based on your actual performance needs. Some materials may be over-qualified for the job when a more affordable material will work just as well, introducing unnecessary costs and production challenges.

For example, an expensive, high-temperature-rated thermal insulator material like aerogel is great for strategic high-performance insulation in small, high-risk areas like cell-to-cell barriers. But due to its high cost and handling challenges, utilizing it across the pack for less critical insulation challenges is not only unnecessarily expensive, but impractical. Polyamide films, medium temperature-rated foams, and other aerogel alternatives are much more affordable options for larger-scale insulation across less demanding areas of the battery pack.  

If we’re continuing with the cookie analogy from earlier, this is the difference between sourcing expensive pure chocolate straight from Switzerland and buying standard chocolate chips from the grocery store when making large batches of chocolate chip cookies for a company-wide work outing. While the store-bought chocolate chips are less decadent, they are much more reasonable and affordable to use in large batches of cookies. And hey, they still taste great! 

Considering Material Properties

Over-specifying extends beyond the type of material used, also translating to material properties like thickness, density, rigidity, and elasticity. These four factors can make tight tolerance cutting much more difficult, leading to unnecessary defects and processing challenges.

Raw materials often come from the manufacturer with certain industry-standard properties. For this example, let's go with thickness. Just running with the standard off-the-shelf thickness without considering what's actually necessary for the functionality of the part negatively affects part quality and increases defects. Consult with your converting partner to determine what material thickness is truly critical for your design to help manufacturing efficiency and prevent costly reworks.  

In the cookie world, this is like rolling your dough too thick, making it difficult for your cookie-cutter to accurately stamp the desired shapes, while also wasting more cookie dough. You should strive to roll your cookie dough thick enough to be structurally sound and not easily break apart, while also thin enough to be efficiently cut and baked without issue. 

Prioritizing Functional Tolerances

While we’re on the topic of tolerance, it’s important to understand the difference between standard “off-the-shelf" tolerances and functional tolerances. Sometimes, engineers may go with certain standard “off-the-shelf” tolerances that may be unnecessarily stringent, leading to manufacturing challenges, increased costs, and defects. 

Functional tolerances are the tolerances that are truly critical to the functionality of your part. Instead of just running with standard tolerances, communicate the needs of your component with your converting partner to ensure you're utilizing truly functional tolerances, helping avoid defects and improve ease of manufacturing.

To get back to our cookie-converting analogy, this is essentially the same predicament as buying the store-bought chocolate chips compared to expensive Swiss Chocolate. It’s a matter of weighing cost and functionality to determine what’s truly necessary and most functional based on your needs. 

JBC Technologies: Adding Value, Subtracting Costs

JBC Technologies is an ISO 9001 Certified full-service custom die-cutter and flexible materials converter with over 35 years of experience providing custom die-cut solutions to the EV battery, energy storage, aerospace, medical, automotive, and industrial markets. Founded on the pillars of supply chain optimization, engineering innovation, and manufacturing excellence, JBC converts a wide range of flexible materials into functional battery components, including thermal and electrical insulation, separators, and pack seals and gaskets. With a range of value-added services and a team of dedicated engineers, JBC provides full product lifestyle support from rapid prototyping to high-volume manufacturing.  

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