Solved! Understand The Differences Between Prismatic and Cylindrical LiFePO4 Batteries
Aug 30, 2023
Electronics and other applications come in vast shapes. They function on battery power battery cells, which also come in different shapes to fit their application and energy necessities.
Lithium batteries can come in three packages: cylindrical, prismatic, and pouch cells. The first two, cylindrical and prismatic cells, are generally made of steel and aluminum cases. They offer specific qualities, either to mass produce or higher capacity range.
We will review the main characteristics, their differences, and why one is taking over the other.
What are LiFePO4 Prismatic Batteries?
This type of battery has a prismatic shape. The prismatic battery´s chemistry is enclosed in a rigid casing. As it has a rectangular shape, it allows efficient stacking of multiple units in a battery unit.
This type of battery is mainly used in energy storage systems and electric vehicles. Since their size is larger than other battery types, they are bad candidates for devices like e-bikes or cell phones. This is why they are better suited for energy-intensive applications.
The prismatic battery shape is a relatively new type. It is said they are the product development of the electric vehicle industry.
As a result of their distinctive construction, the prismatic metal batteries tend to be more skinny, efficient, and easy to connect four cells and create a 12V battery pack.
What are LiFePO4 Cylindrical Batteries?
Cylindrical cells also look as their name implies. It is commonly used in our daily lives and for different applications. They are more amenable to volume production and, as a result, less expensive. They handle the internal pressure quite well. Additionally, similar to the connection in series or parallel (read more here), the battery can continue operating if a cell fails.
They take up more space and are more quickly affected if exposed to temperature swings. The way the cells are built up, they have space and air around them, making it easy to heat or freeze quickly. They are usually employed in portable computer batteries and even EVs.
Difference Between Cylindrical & Prismatic LiFePO4 Cells
Both batteries and their cells have distinctive shapes and can accommodate different devices. Let's have a look at their main differences.
One of the main points in their distinction. The prismatic battery has a square design, making it possible to arrange the cells closely with no gaps. Unfortunately, the cylindrical type will inevitably have gaps due to its shape.
The prismatic cells' contents are pressed together into layers, giving their prismatic shape. As a result, it saves space. On the contrary, cylindrical, round shape is attributed to mechanic stability and an even distribution of electrolytes.
Prismatic cells have a life cycle that averages around 2000 cycles. Opposite to cylindrical, which ranges between 300 to 500 cycles. Prismatics offer an excellent life span even under high and varied loads. This gives a life cycle up to four times greater than cylindrical ones.
Cylindrical batteries are built up in rigid cylinder cans and made of steel. For that, they will be heavier. On the contrary, prismatic cells are larger and do not differ much regarding the weight of cylindrical cells.
When we talk about manufacturing batteries, cylindrical ones are easier to manufacture. This is because the technology for it has been around for generations. As a result, the cost is for these types cheaper.
On the contrary, prismatic ones are more costly to manufacture. There are limitations in the processing technology and no particular standardized production specifications.
An extra note is that each battery's chemistry will also affect the cost. Lithium batteries have, in some opportunities, increased costs due to testing and certifications required.
There is a a high damage cost when it comes to prismatic cells. Since any damage that affects its cells directly impacts the entire pack. Contrary to cylindrical ones. If one cell is damaged, it will not endanger the whole battery pack.
It should also be noted that the cells under which the battery is constructed must be audited under strict ISO standards. When batteries are built with cheaper cells or less severe conditions, a grain of dirt can become a high resistant point and heat the battery. As a result, it can cause a partition or the entire battery to fail.
How cells are linked is also a critical point, which will also affect your decision. The energy density of prismatic is, in theory, higher than cylindrical ones. Prismatic batteries do not use high-strength stainless steel shells like cylindrical batteries. As a result, more electric vehicles apply more for the prismatic battery.
Temperature has a significant impact on batteries and cells. Since prismatic batteries have "sandwiched" their cells, it is more difficult for them to ventilate and dissipate the built-up heat. Contrary to cylindrical ones that have a gap between each cell. However, as it provides heat dissipation benefits, this gap can also build up more quickly at freezing temperatures.
Why Prismatic Cells Might Be Taking Over
Lithium batteries have come to great lengths in the last couple of years. It is still being determined whether prismatic cells or cylindrical will prevail. For the time being, cylindrical are more widespread. Yet, there are some reasons to think that prismatic cells will gain popularity over cylindrical cells.
First, lowering the manufacturing cost. Prismatic cells diminish the number of manufacturing steps. Their format makes it possible to manufacture larger cells. Thus reducing the number of electrical connections.
Prismatic batteries are also ideal for the LiFePO4 chemistry. You can read more about LiFePO4 here. However, the main highlight of these batteries is that they are environmentally friendlier. The resources companies use are found everywhere in the world. Contrary to what occurs with nickel and cobalt in which in some cases slavery is involved.
Both cylindrical and prismatic LiFePO4 batteries have their own advantages and disadvantages. Plus they have distinctive features. From manufacturing to power. The type of LiFePO4 battery will depend entirely on your application. Yet, prismatic cells have started to be widely used. Even Tesla began to adapt the LiFePO4 cells to prismatic.
Consider each type of cell's different characteristics when choosing a battery for any of your devices. Additionaly, you can also check all our other resources regarding Goldenmate LiFePO4 batteries.