# Electrode Dimensions

The cell electrodes are key parts of a battery cell and as such the dimensions of the electrodes are also a key aspect. The electrode dimensions define the area and volume of the active material, hence the overall capacity of the cell.

### Cylindrical Cell

#### Cylindrical Cell Electrode Estimation

Knowing the outer and inner diameter of the spiral along with itâ€™s thickness we can calculate the length of the material to create it.

D is the inner diameter of the cylindrical can.

The inner diameter is that of the mandrel around which we wind the spiral.

#### Alternative Cylindrical Cell Electrode Estimation

Cylindrical Cell Electrode Estimation: An alternative geometric approach.

Here we present a simple method for estimating electrode length in a cylindrical cell. The method is equally applicable to other formats since we make an estimation of the total active electrode area. Results require knowledge of one electrode Active Material (AM) chemistry, electrode porosity and thickness and cell capacity. We assume that 100% of the active material is utilised and contributes to the cell capacity. This is optimistic and will likely lead to an underestimate of the length.

### Prismatic Cell

There are many different types of prismatic cell in terms of the arrangement of the active layers. This impacts a number of parameters, including the electrode dimensions and hence we will need to cover each in turn.

#### Prismatic Cell Electrode Estimation

Using some simple mathematics and dimensions we can do some prismatic cell electrode estimation.