Cylindrical cell VS Prismatic cell VS Pouch cell
There are three types of lithium battery packaging: cylindrical, prismatic, and soft package. Cylindrical batteries, with their cylindrical shape and construction, were one of the first mass-produced battery types and are still mass-produced and dominant in some applications. Prismatic cell batteries, on the other hand, are popular because of their high capacity, thin shape, and efficient use of space. Their prismatic shape makes it easy to connect multiple cells together to form larger packs. Finally, bag batteries are known for their lighter construction with their sealed flexible foil as containers.
There are many types of cylindrical batteries, such as 14650, 17490, 18650, 21700, 26500, etc. Many models use this type of battery; Tesla, for example, uses 21,700 cylindrical batteries for its Model 3.
Cylindrical lithium battery technology has existed for some time, so the output and consistency of battery packs are high. The cost of these packages is also low, making them suitable for mass production. Cylindrical batteries are particularly convenient because of their variety of combinations and applicability to electric vehicle design.
On the other hand, these batteries are often packaged in steel or aluminum cases, making them bulky and low-power.
Cylindrical batteries are commonly found in medical devices, laptops, electric bikes, and power tools. These batteries are also used in Tesla cars.
Prismatic cell batteries are used in consumer electronics and electric vehicles, and their packaging advantage lies in the layered approach to their materials. They are shaped similar to a pack of gum or a small chocolate bar, and while they come in different sizes, there is no universal format and each manufacturer designs its own.
Square lithium battery
The casing of the square lithium battery is made of aluminum alloy and stainless steel. A winding or laminating process is used inside the battery. The structure is relatively simple, the production process is not complicated.
They are safer than cylindrical lithium-ion batteries. Because they do not use the stronger stainless steel housing and accessories with explosion-proof safety valves as cylindrical batteries do, they are lighter overall and have a relatively higher energy density.
Due to the wide variety of lithium batteries, the automation degree is low. The monomers are also very different, and it is possible to have groups of square lithium-ion batteries that have a much shorter life than a single lithium-ion battery.
Soft-pack batteries make efficient use of space and are popular because of their lightweight, simple and flexible design. Typically, soft packs are made of lithium polymers, which are less durable and powerful than lithium-ion batteries found in cylindrical batteries. High humidity and high temperatures can shorten their service life, and the expansion or swelling of soft-pack batteries is their main problem due to the internal gas generation caused by charging and discharging. Each manufacturer makes soft-pack batteries for specific applications, so there are no standards for their size.
Aluminum plastic film packaging has a certain degree of flexibility. In the event of a safety problem, the battery will swell and crack, but it won’t explode or cause a fire because the gas can’t be released.
However, most soft-pack batteries need to be customized. Gateway Power, Grepow, and other manufacturers can customize soft-pack batteries.
Applications include smartphones, drones, wearable devices, the automotive industry, military fields, etc.
In general, cylindrical cells, prismatic cells, and flexible pack batteries each have advantages and disadvantages. Each battery has its own area of excellence and is well used. Here are some of the major pros and cons you should be aware of when considering cylindrical versus soft-pack batteries — of course, the type of battery you ultimately choose will depend on the type of application you need it for.