What Is a Battery? What Does It Do, and What Are the Types of Batteries?

Batteries are the core portable power sources behind many electronic devices used in daily life. From TV remotes to smartphones, countless devices operate thanks to batteries. Batteries vary significantly in form, capacity, structure, chemistry, and usage areas, which makes it easy to find the right battery type for a specific purpose. Let’s explore batteries and their types in more detail.

What Is a Battery?
A battery is a portable energy storage unit that converts chemical energy directly into electrical energy. Batteries store electrical energy chemically through internal components and chemical materials. When these chemicals react, electrical energy is released, allowing the battery to generate power.

What Does a Battery Do?
A battery converts the stored chemical energy into electrical energy through chemical reactions and transfers it to a circuit. With different shapes and internal structures, batteries can power a wide range of devices, including controllers, toys, computers, tablets, smartphones, and even electric vehicles.

How Do Batteries Work?
Batteries generate electrical energy through internal chemical reactions. As long as the chemical materials inside the battery can continue reacting, electricity continues to be produced. Once the chemical resources are depleted, the battery runs out of power.
While non-rechargeable batteries work this way and can no longer produce energy once depleted, rechargeable batteries operate differently. In rechargeable batteries, when the energy production potential ends, an external electrical current is applied to reverse the chemical reaction, allowing the battery to generate electrical energy again.

What Are the Types of Batteries?
Batteries are classified based on usage areas, chemical structure, size, and capacity. Today, when buying a battery, you may encounter names such as AA, AAA, C, D, CR2032, LR44 button batteries, and more. The shape, chemistry, power, and capacity of batteries differ depending on the device they are used in.
Currently, battery types are grouped into 3 main categories:

1. Non-Rechargeable (Primary) Batteries

These are single-use batteries. As the name suggests, there is no way to reverse the chemical reaction once it ends. They are more affordable than rechargeable batteries and suitable for devices with low energy consumption. Examples include clocks and remotes that can operate for long periods.

Common non-rechargeable battery chemistries include:

Zinc Batteries
Widely used in devices such as wall clocks, remotes, and flashlights.

Alkaline Batteries
Store more energy than zinc batteries and are used in devices with higher power needs, such as radios, digital cameras, and gaming devices.

Lithium Batteries
Although single-use, they are preferred for their long lifespan. One of the most common usage areas is computer motherboards.

2. Rechargeable (Secondary) Batteries

These batteries allow the internal chemical reaction to be reversed by applying electrical current. They are more expensive than non-rechargeable batteries, but because they can be reused many times through charge-discharge cycles, they offer a much longer lifespan. Note that each recharge cycle slightly reduces capacity.

Most common rechargeable battery types:

Lithium-Ion (Li-Ion) Batteries
The most widely used rechargeable battery type. Found in modern smartphones, tablets, and portable computers.

Lithium-Polymer (Li-Po) Batteries
Similar usage areas to Li-Ion, but more chemically flammable and requires extra caution when used.

Nickel-Metal Hydride (Ni-MH) Batteries
High-capacity batteries that enable long device usage, but may experience energy loss during long storage.

Nickel-Cadmium (Ni-Cd) Batteries
Lower energy storage capacity than Ni-MH, but does not lose energy quickly during storage, making it suitable for active use.

3. Button Batteries

Button batteries are flat, round, and compact. They can power devices with very low power needs for long durations. They are mostly non-rechargeable, but rechargeable versions also exist.
They are used in a wide range of products such as computer motherboards, wristwatches, scales, and decorative electronics.