**3. The main components of fuel cells**

In addition to the two electrodes and their separator electrolyte, other additional parts are required for specific tasks such as gases flow and electrical insulation or connection. These parts are shown in **Figure 3**.

#### **3.1 The end plates**

The outer sides of the anode and the cathode are supported mechanically by plastic plates which are called the endplates. Their main jobs are to save the fuel cell component and to prevent the reacting gasses from leaking [15].

#### **3.2 The bipolar plates**

A fuel cell has two bipolar plates each one consists of a current collector and separator plate. They are manufactured from a metal or a carbon-filled composite (conductive polymer) [16]. Researchers suggested several designs of

**Figure 3.** *The component of fuel cell [14].*

**Figure 4.** *Various designs of bipolar plates [17].*

the bipolar plate to feed the gaseous fuel to the electrodes uniformly as shown in **Figure 4**. Their designs differ by the shape and the distributions of the gas flow channels.

When many cells are connected in one stack, the bipolar plates conduct current between the adjacent cells. Another function of the bipolar plate is to dissipate the generated heat during the chemical reactions [18, 19].
