A battery is comparable to a tube with metal plates (electrode) in it. This tube is filled with certain chemical substances where a chemical reaction is generated. The battery technology determines the properties of a battery. For example, the capacity, charging time, lifespan and self-discharge differ per type of battery technology.
A battery consists of four elements
- A negative electrode: a negative conductor that accepts energy from an external circuit.
- A positive electrode: a positive conductor that gives off energy to an external circuit.
- A separator: separates the negative and positive electrode.
- Electrolyte: A layer that can quickly transport electrons from one electrode to another electrode.
How a battery works
The operation of a battery is activated when a closed circuit is formed, or a connection between the positive and negative poles of the battery. Connecting a screwdriver or flashlight to a battery forms the connection between the positive and negative poles. In this closed circuit, a reaction occurs at the negative electrode, in which electrons are formed. During this reaction, a reaction also occurs in the positively charged electrode, namely the absorption of electrodes. The positive and negative electrodes consist of different materials and each conduct electrons to the terminals. Now the separator takes on an important role and prevents the electrons from moving between the two different electrodes. The separator only allows the ions to pass through. The electrons can move to the other cell, but only via the external circuit. This leads to a voltage difference, which makes the connected device function.
While this reaction is taking place, a number of other things are happening in the battery. The electrons that flow to the positive electrode via the external circuit enter into a reaction. At the negative electrode, the reaction takes place again, which means that electrons can be released to the external circuit again. This electrochemical process only stops when all electrodes are saturated and no more reaction is possible. The battery is then empty.
During the charging of the battery, exactly the opposite occurs. By supplying electricity, a chemical reaction occurs. The positive electrode is stripped of the negative electrons and the negative electrode is replenished with negative electrons.
What different battery technologies are there for power tools?
- Ni-CD or Nickel-Cadmium
- Ni-MH or Nickel Metal Hydride
- Li-Ion or Lithium-Ion
