Knowledge Hub

Battery pack is more than just battery cells

When we think of lithium-ion batteries, we usually picture the battery cells themselves. In reality, the cells are only one part of a complete battery pack.

Each battery module also consists of numerous precision metal components responsible for electrical connections, mounting, shielding, and the overall safety of the system.

These components are individually designed for each project and manufactured using precision metal stamping technologies.

Some of them include:

• Nickel or nickel-plated contact plates
• Cell connection plates
• Battery connector plates
• Copper busbars
• Nickel busbars
• Spring contacts
• Battery cell holders
• EMI shielding parts
• Mounting brackets
• Grounding contacts
• Battery terminal components

Why are metal components so important?

In a modern battery pack, even several hundred battery cells must be interconnected with extremely low electrical resistance. For this reason, manufacturers use precision-stamped components made from nickel, copper, aluminum, and stainless steel, eliminating additional electrical resistance that would otherwise increase operating temperature, reduce efficiency, and shorten battery life.

How are metal components for battery packs manufactured?

In high-volume battery component manufacturing, precision and repeatability are critical. Metal components for battery packs are therefore most commonly produced using progressive die stamping, precision metal stamping, metal forming, embossing, blanking, and bending.

These advanced metal forming technologies ensure outstanding dimensional repeatability and the highest quality of components required for the reliable operation of modern energy storage systems.

What do battery pack designers focus on?

When designing metal components for battery systems, battery pack engineers place particular emphasis on low electrical resistance and absolute dimensional repeatability, both of which directly determine production process stability.

Burr-free edges and proper flatness are equally important, as these characteristics eliminate the risk of short circuits and enable fully automated battery cell assembly using robotic equipment.

In addition, experienced product designers and process engineers always optimize material utilization, reducing the cost of high-volume production while maintaining the highest standards of safety and energy efficiency.

How does DAGA support battery pack manufacturers?

DAGA designs and manufactures precision stamped metal components for industrial applications. For demanding battery system projects, we support our partners throughout every stage of project implementation.

Our comprehensive offering for the e-mobility industry includes:

• Design for Manufacturability (DFM) analysis: We verify component geometry before tooling is manufactured.
• Optimization for high-volume production: We adapt component designs to the requirements of mass production.
• Progressive die design: We design and manufacture advanced tooling in-house.
• Material waste reduction: We optimize strip layout to directly reduce the unit cost of each component.
• Prototype production: We quickly deliver prototype batches for validation and the assembly of initial battery packs.
• High-volume production: We provide stable and repeatable large-scale production of metal electrical contact components.

Looking for a manufacturer of stamped metal components for battery packs?

If you are designing and implementing:

• Battery packs
• Battery modules
• ESS / BESS (stationary and containerized Energy Storage Systems)
• AGV batteries / Robot batteries
• E-mobility batteries (for electric vehicles, e-bikes, and electric scooters)

Contact the DAGA team during the metal component design phase. The earlier we analyze your component geometry, the greater the savings you can achieve through production cost optimization and efficient material utilization.

Let’s discuss your project

Do you have questions about metal stamping technologies or would you like to discuss your project?

Contact me directly.

Monika Marszałek
New Project Implementation
Email: monika.marszalek@daga.com.pl

“Please send the material certificate.” This is a phrase heard almost every day in the metal industry. The problem is that the term “certificate” can refer to several different documents, while their proper names and meanings are defined by EN 10204. Let’s take a closer look at a document that seems to have acquired more nicknames than the hero of a novel.

At first glance, the matter appears simple: you buy steel, receive a quality document, and the case is closed. Yet the very same document may be referred to by many different names, leaving buyers, quality engineers, and technologists wondering whether they are actually talking about the same thing. Where does this variety of terminology come from?

Whenever a question arises, it is worth going back to the source – in this case, EN 10204:2006. It is a remarkably concise document, only nine pages long. The standard distinguishes just four types of inspection documents. In the past, there were more, and they can still be encountered in companies running long-term projects. That is why I strongly recommend not discarding withdrawn standards – not from your shelves, your computer, or even your memory. They can be extremely helpful when trying to understand older documentation.

But let us return to the current version of the standard and its “big four” inspection documents. They are identified by the numbers 2.1, 2.2, 3.1, and 3.2. One might assume that such a numbering system would virtually eliminate the possibility of confusion. However, the Technical Committee went one step further and assigned different names to these documents as well. In my view, this is where the abundance of colloquial terms used for inspection documents in the metal industry originates.

The human mind naturally seeks simplification. After all, brevity is the soul of wit. Faced with an overwhelming amount of information, we shorten, simplify, and create our own terminology. I can admit that in my daily professional practice I most often use the word “certificate” together with the numerical designation, and I always receive the correct document. That tells me I am being understood. Of course, I use this terminology only in everyday communication. In formal documents such as purchase orders or specifications, I strictly follow the nomenclature defined by the standard.

So, what exactly does the standard say?

Below you will find a table showing the names of inspection documents in four languages. You will see that, according to EN 10204, a declaration, a test report, and an inspection certificate are not the same thing. Enjoy the reading. This knowledge will prove useful both during incoming goods inspection and when placing an order.

Author: Monika Marszałek

To avoid the ambiguity of the question, let us first determine whether we are discussing the product classification or the manufacturing process by which it is produced.

Let’s start with narrow strip.

For the purpose of this discussion, I will assume that we are referring to cold-rolled steel strip intended for cold forming applications, such as the material shown in the photograph below:

The strip in these coils is 85 mm wide (DC01 3 × 85). Does that mean it is narrow strip?

Not necessarily.

How can we determine whether a strip is classified as narrow or wide? The answer can be found in the relevant standards, which I will reference at the end of this article.

For now, let me present a simplified table. It will serve as a guide to help us navigate the topic and understand the direction of our discussion.

The dividing line between strip categories is a width of 600 mm.  Products are classified as either less than 600 mm wide or equal to or greater than 600 mm wide.

It will come as no surprise that narrow strip is defined as strip not exceeding 600 mm in width. However, width alone is not sufficient to classify a product as narrow strip.

Narrow strip is a specific steel mill product that must comply with the requirements of the standards listed in our table — EN 10139 and EN 10140

The term slit coil strip refers to the method by which the material width is obtained, rather than to a specific product category defined by a standard. It describes a product created by longitudinally slitting a wide steel coil into narrower strips.

Therefore, the term itself does not provide any information about the standard according to which the original material was produced at the steel mill, nor does it indicate the width of the parent coil (400 mm, 600 mm, 2,000 mm, or any other width).

To better understand the distinction, let us summarize the concept using the diagram below.

When Do We Use Slit Coil Strip?

In our production processes, we use both narrow strip supplied directly from steel mills and slit coil strip. Contrary to what one might expect, the choice between these two solutions is not always straightforward and depends on a range of technological, logistical, and economic factors.

The most common reason for using slit coil strip is the need for a material width that is not available within the standard product range offered by steel mills. When designing a stamping layout, we select the strip width to maximize material utilization and minimize scrap. This often requires ordering a strip width tailored to a specific component rather than relying on standard mill dimensions.

Slit coil strip is also particularly useful for launching new projects, producing prototypes, and manufacturing small batches. In such cases, ordering full mill quantities for a single strip width is often not economically justified. It is usually far more practical and cost-effective to slit an available coil to the required width.

Another advantage is lead time. Slitting material already available at a steel service center is frequently faster than waiting for a steel mill to manufacture and deliver strip in a specific width.

Inventory management is another important consideration. Slit coil strip allows companies to reduce the number of different strip widths held in stock while maintaining the flexibility to respond quickly to changing production requirements. This approach simplifies inventory management and helps reduce the amount of working capital tied up in stock.

Slit coil strip is also widely used for expensive steel grades, specialty materials, and applications where a single parent coil is intended to supply several different components. In these situations, the ability to slit one coil into multiple widths improves material utilization and contributes to lower overall production costs.

Most often, these services are provided by steel service centers. There are at least a dozen of them on the Polish market, and probably even several dozen. Some specialize in specific steel grades or material groups, but all of them offer coil slitting to widths tailored to the customer’s requirements.

In practice, this is where we order strip widths determined by the die design and the strip layout of the parts.

Similar services are also offered by some steel mills, although I have not personally had the opportunity to use their slitting services.

A press stroke is one complete operating cycle of a stamping press, during which the ram moves downward, the forming or blanking operation is performed in the tool, and the ram returns to its starting position. In practical terms, it represents one machine cycle in which stamped parts are produced.

In stamping die and tool design, the press stroke is a fundamental production unit because it directly defines process efficiency and the cost of producing a single part.

Why does a press stroke affect production cost?

The key parameter is the number of parts produced per single press stroke, also known as tool efficiency (parts per stroke).

• 1 part per stroke → lower efficiency, higher unit cost
• 2–3 parts per stroke → higher efficiency, lower unit cost
• multi-cavity tools → maximum production cost optimization

The more parts produced in one press cycle, the shorter the time required to manufacture a single component. This directly reduces cycle time and lowers serial production costs.

Comparing stamping die offers based only on tooling price is one of the most common mistakes in tool procurement. The purchase price is important, but it does not reflect the costs the tool will generate over years of serial production.

To properly compare offers, it is also essential to evaluate:

Gross Part Weight

Gross weight is one of the key indicators of design quality. It shows how much material is actually consumed to produce one part. Differences in gross weight are usually a direct result of nesting quality and tool layout optimization.

Production Efficiency (Parts per Stroke)

How many parts are produced in one press stroke? The difference between one part per stroke and two or three parts per stroke has a major impact on unit cost and overall production time.

Tool Layout Concept

Is the tool designed to minimize initial manufacturing cost, or to optimize serial production performance in terms of material usage, cycle time, and process stability?

Process Stability and Risk

Lower-cost tooling often comes with higher production risk, such as:

• downtime,
• strip feeding issues,
• higher scrap rates,
• more frequent adjustments and maintenance.

Total Production Cost (TCO)

The key question is not: “How much does the stamping die cost?”
but rather: “How much will it cost to produce one million parts using this tool?”

Summary

The price difference between stamping dies is rarely driven by the part itself. It is mainly the result of how deeply the designer has optimized the manufacturing process. Therefore, when comparing offers, it is essential to look beyond the tooling price alone.

In practice, the quality of the engineering design—nesting, tool layout, production efficiency, and process stability—determines whether the tool will generate long-term savings or hidden production costs during serial manufacturing.

Two stamping dies designed for the same part can differ significantly in manufacturing cost, because the part geometry itself is only the starting point. The final tooling cost depends mainly on how the stamping process is engineered and how well the tool layout is optimized.

The most common reasons for cost differences include:

• the level of nesting optimization and raw material utilization,
• the number of operations integrated into the tool (progressive, stage-wise, or complex multi-operation design),
• the number of parts produced per press stroke,
• the quality and durability of tool components used,
• design assumptions regarding production efficiency and process stability,
• expected tool life (durability vs. initial investment cost).

In practice, one supplier may offer a “cost-minimized” tool concept focused on reducing the initial investment, while another may propose a “process-optimized” solution designed to reduce unit production cost in serial manufacturing. This second approach often requires a higher upfront investment but can significantly improve efficiency, material usage, and long-term production costs.

When quoting stamped metal parts, two terms are commonly used: net weight and gross weight of the stamped part. Although they may sound similar, their impact on production costs is very different.

Net weight refers to the actual weight of the finished component delivered to the customer. It is the weight of the part after all manufacturing operations have been completed, excluding any scrap generated during the stamping process.

Gross weight, on the other hand, represents the amount of raw material required to produce one finished part. It includes not only the material contained in the final product but also the process scrap resulting from the die design, strip width, and nesting strategy used in the tool layout.

Why Is Gross Weight So Important?

For customers purchasing serial production of stamped parts, gross weight is one of the key factors affecting the final product cost. Material often represents a significant portion of total manufacturing expenses, which means that even small improvements in material utilization can generate substantial savings in high-volume production.

For example, two different stamping dies may produce the same component with a net weight of 100 g. However, if the first die requires 120 g of material per part while the second requires only 110 g, the latter reduces material consumption by nearly 10% for every component produced. When production volumes reach hundreds of thousands or even millions of parts, this difference can have a significant impact on the total project cost.

What Determines the Gross Weight of a Stamped Part?

The gross weight of a part is directly related to the stamping die design and the optimization of the tool layout. The most important factors include:

• part arrangement within the material strip (nesting),
• strip width,
• the number of parts produced per press stroke,
• carrier and web dimensions,
• stamping process requirements and strip feeding conditions.

An experienced die designer evaluates multiple layout alternatives to achieve the lowest possible gross weight while maintaining a stable, reliable, and efficient production process.

In many projects, the difference between net weight and gross weight provides a clear indication of how efficiently the stamping die has been designed and what the actual production costs will be throughout the entire service life of the tool.

Nesting is one of the key stages in the design of stamping and blanking dies. It consists of optimizing the arrangement of parts within the tool layout to maximize material utilization, reduce scrap, and achieve high production efficiency in serial manufacturing.

During the die design process, the tool designer evaluates various part arrangements within the material strip. The objective is to find a solution that achieves the lowest possible gross part weight while meeting all technological requirements of the stamping process. In practice, even minor changes to the tool layout can result in significant material savings in high-volume production.

For customers ordering a stamping die or sheet metal stamping services, nesting has a direct impact on the cost of the finished product. The better the tool layout is optimized, the lower the material consumption, the smaller the amount of scrap generated, and the more competitive the unit price of the stamped part.

It is also important to remember that a well-designed nesting strategy affects not only material utilization but also production efficiency. In many cases, an optimized tool design allows two, three, or even more parts to be produced in a single press stroke. This translates into shorter production times and lower manufacturing costs per part.

How to Compare Tooling and Serial Production Quotations?

When evaluating suppliers, it is worth looking beyond the tooling price alone. Another important indicator is the gross part weight, which reflects the amount of material required to manufacture a single component.

Comparing gross part weights across different quotations provides valuable insight into how effectively the tool layout and nesting have been optimized. A lower gross part weight generally indicates reduced material waste, better raw material utilization, and lower serial production costs throughout the entire service life of the die.

For this reason, when assessing stamping die and blanking die designs, it is important to consider not only the initial tooling investment but also the long-term production costs the tool will generate over many years of operation. In many projects, the quality of the nesting design is one of the key factors determining the overall competitiveness of the manufacturing process.

Stamping is one of the cold metal forming techniques. It is most commonly used to process metal strips or sheet metal made from materials such as cold-rolled steel, stainless steel, aluminum, copper, or brass. The process is carried out using various types of presses, including mechanical (eccentric), hydraulic, and press brake machines.

To manufacture a component with a specific shape using stamping operations, it is first necessary to design and produce a suitable stamping die based on the technical drawing and the customer’s requirements, including quantity and quality specifications. The die is then installed in the press, enabling the production of parts with highly complex geometries and very tight dimensional tolerances. The most common operations used in the stamping process include blanking, trimming, bending, forming, punching, flanging, upsetting, marking, and embossing.

Every stamping plant or metalworking facility has its own specialization and provides services based on the capabilities of its machinery. DAGA primarily manufactures components using mechanical and hydraulic presses with capacities ranging from 80 to 250 tons. Its portfolio extends beyond projects involving the most common stamping materials, such as mild carbon steel. The company also has many years of experience in the serial production of components made from coated semi-finished materials, including galvanized steel and tin-plated copper, as well as stainless steel alloys.

As an example of DAGA’s more demanding projects, the company has been supplying components for the automotive industry for over 15 years. These include copper electrical circuit components for heavy-duty vehicles and engine oil level indicators for passenger cars, stamped from rolled stainless steel wire.

The production process for a particular component is designed by a manufacturing engineer who takes your specific requirements into account. From a technical perspective, the same product can often be manufactured in several different ways. To determine the most efficient solution, the manufacturer must understand the expected production volume throughout the entire lifecycle of the project.

This is because the most significant cost factor in production preparation is the design, manufacture, and maintenance of the stamping die throughout the production cycle. For medium- and high-volume production, the most cost-effective solution is usually a progressive die. Thanks to its specialized design, multiple operations can be performed simultaneously while maintaining tight dimensional tolerances. This ensures consistent quality, high productivity, and the lowest possible unit production cost.

For lower production volumes, DAGA typically recommends alternatives to progressive stamping. From an economic standpoint, it may be more advantageous to use one or more single-station dies or to combine laser cutting of sheet metal with bending operations performed on press brakes or dedicated bending machines.

Corrosion protection of metal components manufactured through stamping is one of the key factors in maintaining quality when processing steel. Particular attention should be paid to the production of parts made from carbon steel grades such as DC01, DC04, and DD11, which are the least resistant to oxidation. These materials are the most susceptible to rust formation.

Corrosion prevention begins at the raw material preparation stage in steel service centers. Metal strips cut to the required dimensions are supplied with a protective oil film that provides the first layer of protection against corrosion.

In addition, as is the case at DAGA, products are stored in enclosed warehouse facilities until they are transferred to subsequent production processes, minimizing exposure to moisture and temperature fluctuations.

If your project requires additional corrosion protection of the finished component, such as electroplating, chemical surface treatment, or painting, DAGA can also provide these services through its long-standing network of trusted subcontractors.

The material used in stamping operations must not only match the intended purpose (function) and operating conditions of the products manufactured from it. It must also meet the technological requirements related to the deformations necessary to achieve the final geometry of the component. To select a material with the best forming properties from a stamping perspective, we recommend focusing first on its plasticity indicators (e.g., tensile strength Rm and yield strength Re).

Considering the formability and elasticity of stamping materials, they can be divided into the following main groups:

• Low-formability materials – medium-carbon steels, e.g., high-carbon structural steel
• Moderate-formability materials – e.g., chromium-nickel steels, heavily work-hardened aluminum
• Highly formable materials – low-carbon steels (including commonly used grades such as DC01 and DC04), brass, aluminum
• Very highly formable material – copper and titanium alloys.

If you are unsure during the design phase which material from a given group should be specified, contact a DAGA process engineer, who can help you evaluate the advantages and disadvantages of individual solutions. In some cases, only one out of ten manufacturing operations may require a steel grade with enhanced properties. For example, DAGA recommends using steel with improved forming characteristics—at least DC04—for components that require flange-forming operations combined with wall thinning.

When components must withstand exposure to weather conditions, acids, or alkaline solutions, it is worth considering one of the many available specialty steel grades. Stainless steel, including acid-resistant grades, is the preferred material for manufacturing household appliance components, medical instruments, and parts used in the food processing industry. In addition to the material’s technical specification, its cost is also an important consideration. Low-volume production based on expensive or hard-to-source materials may make it more difficult to secure suppliers and can negatively affect the overall return on investment of the project.