03/07/2022
A prismatic cell is a cell whose chemistry is enclosed in a rigid casing. Its rectangular shape allows efficiently stacking multiple units in a battery module. There are two types of prismatic cells: the electrode sheets inside the casing (anode, separator, cathode) are either stacked or rolled and flattened.
The EV industry evolves quickly, and it’s uncertain whether prismatic cells or cylindrical cells will prevail. At the moment, cylindrical cells are more widespread in the EV industry, but there are reasons to think prismatic cells will gain in popularity.
First, prismatic cells offer an opportunity to drive down costs by diminishing the number of manufacturing steps. Their format makes it possible to manufacture larger cells, which reduces the number of electrical connections that need to be cleaned and welded.
Prismatic batteries are also the ideal format for the lithium-iron phosphate (LFP) chemistry, a mix of materials that are cheaper and more accessible. Unlike other chemistries, LFP batteries use resources that are everywhere on the planet. They do not require rare and expensive materials like nickel and cobalt that drive the cost of other cell types upward.
There are strong signals that LFP prismatic cells are emerging. In Asia, EV manufacturers already use LiFePO4 batteries, a type of LFP battery in the prismatic format. Tesla also stated that it has begun using prismatic batteries manufactured in China for the standard range versions of its cars.
The LFP chemistry has important downsides, however. For one, it contains less energy than other chemistries currently in use and, as such, can’t be used for high-performance vehicles like Formula 1 electric cars. In addition, battery management systems (BMS) have a hard time predicting the battery’s charge level.
When it comes to battery pack production demand, energy storage systems (ESS) are just as important as electric vehicles. ESSs are already using prismatic cells and it is very likely that they will keep using them. Prismatic cells have a longer cycle life, are less dangerous, and come at a low cost compared to cylindrical cells.