Due to their different cell manufacturing processes, lithium batteries are divided into three packaging forms: cylindrical, prismatic, and pouch. With their cylindrical shape and construction, cylindrical batteries were one of the first mass-produced battery types. Prismatic cells are popular for their high capacity and thin profile, and due to their prismatic shape, multiple cells are easily connected to form larger battery packs. Pouch cells are known for their lighter construction with their sealed flexible foil as containers. Each package has its own characteristics, reflecting the advantages and disadvantages of different types of lithium battery performance.
Snepow provides the best indoor and outdoor energy storage solutions with advanced battery technology. We pay attention to the development of batteries all the time, so we have made a summary of three packaging forms.
Cylindrical cells are the most common cell type in use today. In 1992, Japan's SONY company developed the cylindrical batteries 18650. There are many types of cylindrical batteries, such as 14650, 17490, 18650, 21700, 26500, etc, which are named after the battery size. Many models use this type of battery, for example, Tesla uses 21,700 cylindrical batteries for its Model 3.
Cylindrical cells are high-voltage resistant, less prone to deformation, and have a strong ability to withstand high internal pressure. They are widespread and standardized, offering a more robust automation process and better manufacturing techniques. On the other hand, cylindrical batteries have formed a series of internationally unified standard specifications and models, with low cost and mature technology, suitable for large-scale continuous production.
Such small battery has large heat dissipation area than prismatic, but a bit complex to form system and comparatively low reliability after system composition. And they are often packaged in steel or aluminum cases, making them bulky and low-power.
Medical devices, laptops, electric vehicle.
Prismatic cells are currently the most widely used batteries in the field of electric vehicles, such as BYD, Geely, Audi, and BMW. With the development of automobile power batteries in recent years, the contradiction between the cruising range of automobiles and battery capacity has become increasingly prominent. Different from cylindrical batteries, square batteries have a simple structure, without accessories such as stainless steel casings and explosion-proof safety valves. So the battery is light in weight and high in energy density.
Prismatic cell batteries are safer than cylindrical. The main characteristics of prismatic lithium battery: the shell is made of aluminium alloy, stainless steel and other materials, with high structural strength, good mechanical load-bearing capacity. On the other hand, the cell capacity and volume of a prismatic battery are larger, so the number of cells is reduced, and the requirements for the BMS battery management system are also reduced. Compared with cylindrical batteries, prismatic batteries are more customizable and more efficient in space utilization.
Prismatic cells can be quite costly to manufacture, coming with a higher watt-per-hour price point. On the other hand, prismatic cells are that if an issue arises with any one cell in a battery pack, the entire pack will be in trouble. Prismatic cells don`t come in a uniform and standard design. However, with the introduction of the country's battery standard policy, the difference in square batteries will also decrease in the future.
Electric vehicles, communication base stations, energy storage, medical and other fields.
Pouch cells are popular because of their lightweight, simple and flexible design. They lack aluminum or steel casing, and are enclosed in a soft polymer aluminum plastic film or shell, which makes them very lightweight. Pouch cell batteries are increasingly popular with smartphone manufacturers with their high energy density and long cycle life.
The soft aluminium coating allows for a more lightweight battery and depending on the use, an adaptable size and available space. This leads to flexible cells that can easily fit the available space of a given product. In terms of space optimization, this translates to between 90%-95% packaging efficiency and increased energy density. By moving to more convenient designs, pouch cells have the potential to match the next-generation performance batteries to accelerate the electrification needs of EVs and consumer electronics. The design is flexible, the shape can be changed into any shape, it can be thinner, it can be customized according to the needs of customers, and new cell models can be developed.
Swelling or expansion is their main problem of pouch cell batteries. High humidity and high temperatures can shorten their lifespan. They are high cost, have relatively poor mechanical load-bearing capacity, and are prone to damage and leakage.
Smartphones, drones, ultra-thin laptop,wearable devices, automotive industry, military fields, etc.
Comparing Cylindrical Cells with Prismatic Batteries and Pouch Cells
In Conclusion, cylindrical cells, prismatic cells, and flexible pack batteries each have advantages and disadvantages. Every battery has its own area of excellence ---let's compare cylindrical cells, prismatic cells, and pouch cells in more depth.
|Steel Shell/Aluminum Shell
|Steel Shell/Aluminum Shell
|Battery Pack Efficiency
High energy density
High degree of customization
Great protection to cell
High efficiency of battery pack
Mature production process
High requirement on production process
No standard design
Low efficiency of battery pack
Low energy density