Recently, we have always received the question from our customers that Lithium Cylindrical vs. Prismatic vs. Pouch Battery Cells, what kind of battery cell should we choose? What are their advantages and disadvantages? Which is cheaper to use? In the face of various application, it is intuitive and important to choose a suitable battery. In this article, we’ll take a look at the core differences between cylindrical, prismatic and pouch cells for batteries to understand how they interact with other tools and devices. Review a comparison of cylindrical cells with pouch cells and prismatic cells , looking at the pros and cons of each type of battery packaging style, and learn some of the industrial uses that each kind of cell is best suited for.

Cylindrical Lithium Battery or Lithium ion Cylindrical Cells

A cylindrical cell consists of sheet-like anodes, separators, and cathodes that are sandwiched, rolled up, and packed into a cylinder-shaped can. This type is one of the first mass-produced types of batteries and is still very popular. These cells are suited for automated manufacturing. There are many types of cylindrical cells, such as 18650, 21700, 26650, 32650/32700 and so on. Many car models use this type of battery; Tesla, for instance, uses a 21700 cylindrical battery for car battery.

1.Lithium ion Cylindrical cells are the most widely used cells for battery packs, the unique design of cylindrical cell helps to minimize the chances that the electrode material inside will break up, even under the heaviest of use conditions.

2.The technology behind cylindrical lithium batteries have been around for quite some time, so the yield and consistency of the pack is high. The cost of these packs are also low, which allows them to be suitable for mass production.

3.Cylindrical cells can support the automation techniques during manufacturing, therefore, it could be produced much faster keeping a lower ultimate cost and help increase the consistency of battery. Due to the benefit from a much faster production rate, a cheaper price, cylindrical cells are an economical choice for various applications such as scooter, ebike, electric motorcycle and also RV campers. So as RV, marine batteries, many factories use 26650 or 32650 cylindrical cells to make 12V 12Ah-200Ah battery packs. Cylindrical cells do have the advantage of flexible capacity design. We can make any desired capacity to meet customers' needs. In addition, Cylindrical cells tend to be more reliable. They burn less energy which results in a higher battery range. Tesla is working on the 4680 cells  in the meantime. Those cells have a 46mm diameter and are around 80mm in length. Tesla has made a big deal out of its new 4680 battery cell design, claiming it will both increase the range of its vehicles and reduce the cost-per-kilowatt of its battery packs. We have to say Elon Musk is the pride of lithium batteries, let's look forward to it.

However, cylindrical cells have a relatively small capacity. To make a large-capacity battery pack, dozens or hundreds of cells are required, and the structural requirements are high. If it is not welded well, or the voltage, capacity and inner resistance are not matched  very well, its a big thing to repair. Therefore, if your battery pack wants to choose cylindrical cells, you must require the supplier to strictly group to ensure the consistency of the internal cell voltage and internal resistance capacity.

Prismatic Lithium Battery Cell

The packaging shell of a prismatic lithium battery is mostly made of aluminum alloy and stainless steel. The inner part of the battery adopts a winding or laminating process. The structure is relatively simple, and the production process is not complicated.

Compared with cylindrical lithium batteries, these batteries are safer. Because they are not like cylindrical batteries that use higher strength stainless steel as the shell and accessories with explosion-proof safety valves, the overall weight is lighter, and the energy density is relatively higher. However, there are some prismatic cell constructed with plastic outer cases. The type of plastic varies, and the cheaper cells use lightweight plastics of the cheapest composition available. The casing is an important point if there are problems with the Lithium cell. The melting point of cheaper plastics can be as low as 150C. Even hard case prismatic cases using better ABS plastic have a melting point of 200C. We need to know melting point of plastic cases is very important. If a Lithium cell is damaged or has a manufacturing fault, then it can go into error. Cheaper cells manufactured under less strict conditions may get something as simple as a single grain of dirt encapsulated in the cell which becomes a high resistant point and will heat up and can cause a cell to fail. Therefore, it is critical to choose cells which are constructed, and systems audited under strict international ISO standards to ensure these manufacturing issues don’t occur.

The safest alternative is utilizing hard case metal cell enclosures. Aluminium has a melting point of 660C. A substantially higher temperature than the 200C of the plastic cell cases and the battery outer cases. Aluminium enclosures are harder to penetrate and do not provide fuel like plastic does. The outer battery case acts as the second layer of protection and when made of hard metal like Aluminium, it will be less likely to fail and allow the rush of oxygen in.

According to our survey, almost 50% of factories choose square/prismatic cells to customize battery packs for RVs, boats, golf carts, home energy storage(ESS), Telecommunication stations and forklift. CATL, CALB, EVE Prismatic cells are good choices. With high capacity of a single cell, assembling a battery pack only takes few cells, which is easier to assemble.In our next article, we will write an article about the assembly methods of the battery pack. If you are interested, please pay attention to our website www.osnpower.com, more interesting and professional battery knowledge will come to you. 

Pouch Lithium Battery Cell

There is little differentiation between the positive electrode, negative electrode material and separator that are used in pouch cell lithium batteries, cylindrical and prismatic lithium batteries. The biggest difference between them is the packaging material, aluminum-plastic film.

The packaging materials are usually divided into three layers: the outer barrier (usually an outer protective layer composed of nylon BOPA or PET), the middle barrier (a middle layer consisting of aluminum foil) and the inner layer (a multifunctional layer). The aluminum-plastic film packaging has a certain degree of flexibility. When a safety problem occurs, the pouch cell battery will bulge up and crack but will not explode or cause a fire because the gas cannot be released. However, most pouch cells need to be customized specially, they are not ready in stock, so lead time is a key point. If you want to develop your own brand, customize a battery cell that is only for you, and build your own brand battery pack from the inside to the out, this is also a way to expand the company's influence.

When selecting suitable lithium cells for your Lithium Battery, please take the below checklist into consideration:

• Cylindrical vs. Prismatic vs. Pouch Battery Cells, what cell the manufacturer use? How they assemble
• If its lithium prismatic cell, Is it enclosed in an Aluminium outer case
• Are the cells made by a manufacturer with international ISO accreditation
• Are the cells compliant with 62619 international standards
• Is the final assembly gone through charge and discharge tests during an audible QA system
• Is the battery passed Triple Guard Protection (Hard case metal cell protection, Electrical BMS protection, and hard case metal outer battery enclosure)

OSN POWER Lithium Batteries are produced with all the above elements and strict QA testing. Through the above analysis, we hope to help more customers make correct judgments and find  suitable cells for their own applications. We also welcome every battery enthusiasts or customers express their opinions to us, please contact support@osnpower.com or service@osnpower.com for help and inquiry.