A battery cell can look quite different depending on its design. They are not all uniform in shape or size; rather, they come in a few common form factors. Here's a breakdown:
Common Battery Cell Form Factors
Battery cells are primarily designed in three main shapes: cylindrical, prismatic, and pouch. These variations cater to different needs and applications.
Cylindrical Cells
- Description: These are the most commonly recognized battery cell shape, resembling a small metal can. They are often found in smaller electronic devices.
- Characteristics:
- Robust and mechanically strong
- Cost-effective to produce
- Standardized sizes available, such as 18650 and 21700.
- Examples: Commonly used in laptops, power tools, and electric vehicles (in battery packs).
Prismatic Cells
- Description: Prismatic cells are rectangular or block-shaped, designed for efficient space utilization.
- Characteristics:
- Good thermal performance
- Efficient stacking in battery packs
- Easier integration into devices with flat surfaces.
- Examples: Frequently used in smartphones, tablets, and some electric vehicles.
Pouch Cells
- Description: Pouch cells are flexible and are enclosed in a foil-like pouch. They can be molded into various shapes, often flatter than cylindrical or prismatic cells.
- Characteristics:
- Lightweight and flexible
- High energy density
- Can be customized to fit specific designs.
- Examples: Popular in mobile devices, wearables, and electric vehicles.
Internal Structure
It's important to remember that while the outer form may vary, the fundamental inner structure of these cells consists of layers or wound sheets of electrodes, separators, and electrolyte. According to the provided reference, the electrode-separator compound has variations in dimensions and manufacturing processes across the different cell designs.
Summary Table
Cell Type | Shape | Common Uses | Key Features |
---|---|---|---|
Cylindrical | Cylinder | Laptops, Power tools, EVs | Robust, cost-effective, standardized |
Prismatic | Rectangular | Smartphones, Tablets, Some EVs | Efficient stacking, good thermal perf. |
Pouch | Flexible pouch | Mobile devices, wearables, EVs | Lightweight, flexible, high energy |