Prismatic cells are also making critical inroads into larger formats. Packaged in welded aluminum housings, the cells deliver capacities of 20 to 30Ah and are primarily used for electric powertrains in hybrid and electric vehicles. Figure 4shows the prismatic cell.
The prismatic cell requires a slightly thicker wall size to compensate for the decreased mechanical stability from the cylindrical design, resulting in a small capacity drop. Optimizing use of space makes up this loss. Prismatic cells for portable devices range from 400mAh to 2,000mAh.
Prismatic cells are contained in a rectangular can. The electrodes are either stacked or in the form of a flattened spiral. They are usually designed to have a very thin profile for use in small electronic devices such as mobile phones. Prismatic cells provide better space utilization at the expense of slightly higher manufacturing costs, lower energy density and more vulnerability to swelling, but these are minor effects which don't constitute a major disadvantage.
The prismatic cell improves space utilization and allows flexible design but it can be more expensive to manufacture, less efficient in thermal management and have a shorter cycle life than the cylindrical design.