Battery cell manufacturing has become one of the fastest-growing industries today. This comes as no surprise, given that battery technologies are present almost everywhere, from consumer electronics to electric vehicles.
In fact, a 2022 analysis shows that the lithium-ion (Li-ion) battery chain could grow up to 30% a year between 2022 and 2030, reaching a value of over $400 billion. What’s more, lithium-ion batteries are currently one of the preferred storage options for renewable energy.
To better understand the current state of this industry, let’s take a deep dive into the process of battery cell manufacturing, from raw material acquisition to assembly. We’ll also explore the latest innovations in the industry and give insights into the trends that are shaping tomorrow’s energy solutions.
The Battery Cell Manufacturing Process: An Overview
We often take batteries for granted—until they run out of juice. After all, they operate quietly in the background, powering the technologies that allow us to function day in and day out. While Li-ion batteries serve a simple purpose, the process of manufacturing this battery technology is meticulous. Let’s walk through the steps involved in production.
Raw Material Acquisition
The lithium-ion production process begins with the procurement of raw materials. These include minerals like lithium, cobalt, nickel, copper, aluminum, manganese, and graphite. Manufacturers can source these elements from a trusted supplier or recycle them from spent batteries. Bigger companies may also venture into mining or partner with mining companies.
This stage often includes the first layer of quality control. Many manufacturers test for purity, chemical composition, particle and particle size distribution, among other aspects. Some companies also implement traceability measures to ensure compliance with regulatory requirements.
Electrode Manufacturing
In this stage, the raw materials are transformed into electrodes. This typically involves the following processes:
- Slurry Mixing: The materials for anodes and cathodes are combined to form a slurry. This includes mixing active materials, binders, and conductive additives thoroughly to ensure uniform particle distribution.
- Coating: Once the slurry is ready, it’s coated onto a substrate material. This could be aluminum for cathodes or copper for anodes. The coating process may involve techniques like doctor-blade coating, slot-die coating, or roll-to-roll coating to control the thickness of the electrode layer.
- Drying: After the coating process is complete, you must dry the electrode to solidify the active material and binder mixture. The most common ways to achieve this are convection drying, vacuum drying, and infrared drying. The ideal technique will depend on the desired electrode properties.
- Calendaring: For battery cells that require a denser and more compact electrode layer, the dried electrode may undergo calendaring. This entails passing the electrode through rollers to compress the material. This can also improve its adhesion to the substrate.
- Cutting and Sizing: After the steps above, the electrode is then cut into specific sizes and shapes to fit the dimensions of the battery cell design.
Battery Cell Assembly
In the cell assembly stage, manufacturers combine all the prepared components of the battery cell: the electrodes, separator, and electrolyte. It usually entails the following steps:
- Winding or Stacking: Depending on the type of battery you want to build, you would stack or wind together electrodes and separators. Cathodes and anode electrodes are layered in an alternating manner with separators in between. From here, you can form them into either a cylindrical or prismatic shape.
- Terminal Welding: In this step, you establish electrical connections between the electrodes and the external terminals. It requires you to solder the electrode tabs to ensure a reliable connection. This can also help prevent overheating and damage later on.
- Encapsulation: Also known as canning, encapsulation involves enclosing the electrode assembly and electrolyte in a protective housing to form the final battery cell. Depending on the design, manufacturers can use aluminum, steel, metal, plastic, or polypropylene to make the casing. This process is typically automated.
Battery Cell Finishing
The final stage of battery cell manufacturing is cell finishing:
- Filling: Upon assembling the battery cell, you then fill it with electrolytes. It’s important to carefully control the filling. This way, you can ensure that it’s evenly distributed throughout the cell.
- Formation and Sealing: The battery cells will undergo a series of charge and discharge cycles to activate the electrodes. This is important to remove impurities and stabilize the cell’s performance.
- Labeling and Marking: When the assembly is complete, users can place their identification labels, markings, and barcodes.
- Ageing: This process exposes the battery cells to high temperatures and repeated charging to simulate how it can potentially change over time. Doing so is particularly helpful in predicting how each battery should perform.
- Final Quality Check: Once you complete the battery cell, you must conduct control checks, such as on the battery’s mass and dimension. It’s also critical to ensure that there are no anomalies in terms of its surface, tab, or seal.
Types of Battery Cells
Lithium batteries come in different types and sizes. Below, we’ll explore prismatic cells, cylindrical cells, and pouch cells. We’ll also look at their different applications and advantages.
Prismatic Cells
Prismatic cells are a type of rechargeable battery cell that has a rectangular or square shape. The battery cell manufacturing process for prismatic cells involves stacking or rolling and then flattening electrodes. As a result, it has a higher energy density and more efficient use of space.
Unlike cylindrical cells, prismatic cells don’t require additional casing, which gives them a more streamlined and space-saving structure. Compared to pouch cells, prismatic battery cells are more durable and can be more cost-effective to manufacture.
Because of its compact design and longer battery life, prismatic cells are suitable for energy-intensive applications that require lightweight power sources. You can also arrange them in custom configurations to fit specific device dimensions.
You typically use these cells in:
- Consumer electronics like smartphones and laptops
- Electric cars, golf carts, and motorhome batteries
- Energy storage systems for solar power plants and wind farms
- Medical equipment in both clinical and home healthcare settings
- Industrial applications like robotics, unmanned aerial vehicles, and automation systems
- Smartphones and laptops
- Backup power systems
Cylindrical Cells
Cylindrical cells, as the name suggests, have a cylindrical shape. They resemble traditional AA or AAA batteries. This is one of the first mass-produced types of lithium batteries and is currently the most commonly used.
This type of lithium-ion battery typically features a metal casing, which gives it added protection against physical damage and thermal runaway. Also, its standardized dimension makes it easy to integrate into existing battery pack designs.
But compared to prismatic and pouch cells, cylindrical cells typically store less energy per unit volume or weight. In addition, they must be packaged in steel shells when combined into battery packs. As such, cylindrical cells can be relatively heavier than other cell types.
Cylindrical cells are often used in:
- Consumer electronics like smartphones, laptops, and digital cameras
- Flashlights and rechargeable lighting fixtures
- Cordless power tools like drills and screwdrivers
- High-performance electric sports cars
- Portable defibrillators and diagnostic equipment
- Satellites, drones, and military equipment
Pouch Cells
Pouch cells are a type of lithium-ion battery with a flat, flexible structure. While these may look similar to prismatic cells, they’re enclosed in an aluminum-coated plastic film. This gives them a smaller profile and maintains high energy efficiency and power delivery.
Unlike cylindrical or prismatic cells, which come in rigid casings, pouch cells can be made to fit in limited space or specific device dimensions. Due to the nature of its materials, it’s also lighter, so it’s ideal for applications where weight is a concern.
However, the traits that make pouch cells beneficial also add to their disadvantage. For instance, its lack of solid packaging makes it vulnerable to punctures. Its thin structure also gives it limited thermal management capabilities, which can degrade battery performance and pose safety risks. In addition, its customizable design can make it more complex and expensive to manufacture.
You usually see pouch cells in:
- Consumer electronics with unconventional shapes like e-cigarettes
- Internet of Things (IoT) devices and household electronics like smoke detectors
- Electronics that need high load currents like drones
- Wearable devices like smartwatches and smart glasses
- Portable diagnostic equipment and medical devices like infusion pumps
Trends in Battery Cell Manufacturing in 2024
The battery cell manufacturing process is ever-evolving. The latest industry trends include advancements in materials and production techniques and the integration of renewable energy systems and sustainability practices.
These trends are driving significant changes in the way batteries are manufactured, paving the way for a greener and more energy-efficient future.
Exploration of New Materials
Lithium-ion batteries are currently unmatched in sustainability and efficiency. However, to expand the horizons of battery technologies and capabilities, companies are investing in the exploration of new materials for battery cell manufacturing. These include sodium-ion batteries, iron-air batteries, zinc-based batteries, and saltwater batteries.
Advancements In Production Techniques
New manufacturing techniques are optimizing the production process to increase efficiency and reduce costs, specifically, the unique dry electrode process developed and utilized by Dragonfly Energy.
Dragonfly Energy is revolutionizing cell manufacturing by leveraging decades of expertise, cutting-edge equipment, and data-driven insights to optimize battery performance at a fundamental level. Our unique dry electrode process is chemistry agnostic and requires less space for equipment, allowing for efficient production for both small and large facilities. This innovative approach ensures reliable and scalable battery production that is ready to power the future.
- 25% less energy intense production process
- Lower process-related costs
- 9% reduced carbon footprint for total cell manufacturing
- No Toxic NMP Solvent for more sustainable battery production
- PFAS-Free Electrodes produced
- 22% smaller manufacturing footprint
With the adoption of these techniques, manufacturers like Dragonfly Energy can enhance operations and scale up battery production capacity.
Implementation of Sustainability Practices
As we’ve mentioned, there’s a growing emphasis on sustainability throughout the battery manufacturing supply chain. So, it’s no surprise that recycling initiatives are gaining traction to recover valuable materials from spent batteries.
This strategy aims to reduce the impact of extracting virgin material and mitigate the environmental problems it may cause. These aside, manufacturers are also beginning to implement production techniques that minimize their carbon footprint in the long run.
The Future of Battery Technologies
The demand for sustainable, efficient, and reliable energy storage solutions is shaping the future of battery cell manufacturing. With this in mind, we can expect the coming years to bring about numerous innovations and industry changes, such as:
Increased Research and Development of Solid State Batteries
Solid state batteries represent a significant leap forward in battery technology. They replace the liquid or gel electrolytes found in traditional batteries with solid electrolytes. As a result, solid state batteries offer enhanced safety, higher energy density, and faster charging capabilities. They can also decrease carbon emissions by as much as 39%.
Dragonfly Energy’s unique dry electrode manufacturing process enables our development of nonflammable all-solid-state batteries. As research and development efforts continue, solid state batteries will likely become more widespread. This could revolutionize the energy storage landscape.
More Focus on Recycling Initiatives
The shift to lithium-ion batteries has been pivotal in implementing greener energy practices, but it’s merely the first step toward sustainability. In recent years, more recycling initiatives have been rolled out to minimize the extraction of raw materials. After all, batteries made with recycled materials have four times lower emissions than those made with virgin materials.
Dragonfly Energy has successfully used high-purity lithium hydroxide recovered by Aqua Metals from recycled lithium-ion batteries to manufacture a lithium-based battery cell using Dragonfly Energy’s patented dry battery electrode coating technology. The process demonstrates a potential path towards a more circular and sustainable lithium battery manufacturing industry that addresses the finite and costly nature of battery materials.
Another example of these initiatives is the U.S. Inflation Reduction Act of 2022, which grants tax credits for recycled battery materials. Similarly, Toyota’s battery recycling network aims to foster a closed-loop battery ecosystem nationwide.
Better Integration With Renewable Energy Systems
As renewable energy sources like solar and wind power become more prevalent, there’s a growing need for energy storage solutions to manage the intermittency of these sources. Batteries play a crucial role in integrating renewable energy systems into the grid. They store excess energy during periods of low demand and provide backup power in times of high demand or when renewable energy generation is low.
As a result, we expect the near future to bring an increase in the development of resilient batteries tailored to meet the evolving needs of emerging technologies.
Empower a Greener Future With Li-Ion Battery Cells
Understanding battery cell manufacturing processes is vital to appreciate the intricacies behind the devices that power our modern world. It can also help anticipate future developments and innovations in the battery industry.
What’s more, keeping up with these battery cell manufacturing advancements can make it easier to implement energy-efficient technologies. With a commitment to making sustainable energy solutions more accessible, Dragonfly Energy offers deep-cycle lithium-ion batteries for various applications. By partnering with Dragonfly Energy, you can access cutting-edge battery technology designed to power a greener future.
Take the next step toward sustainable energy solutions with a reliable battery manufacturer at your side. Contact Dragonfly Energy today for more information.
