Battery Definition | Key Components, Working Principle, Types & More

Do you want to understand the actual battery definition? You have landed the perfect guide.

As you know, all portable devices are powered by batteries, such as laptops, mobile phones, cameras, watches, and a range of other electronic gadgets. Can you imagine a world without batteries? All these portable devices would disappear.

Though batteries are there for hundreds of years, many of us are still not fully aware of what they are and how they work. This is where this read comes in handy. It presents the definition of a battery, key components, the working principle, types, technical terminologies, and more. Let’s explore this subject in detail.

What is a battery?

A device that is designed to convert chemical energy into electrical energy is commonly called a battery. The chemical energy is stored in the active material of the battery. An electrochemical oxidation-reduction reaction is something that makes this energy conversion possible. In this reaction, electric current transfers electrons from one material to the other one.

In other words, an electrochemical device that is charged with an electric current and can be discharged as and when needed is known as a battery. The actual battery meaning is cell - an electrochemical unit that stores or generates electric energy.

Are you concerned about the difference between a battery and a cell? You can consider a battery as a combination of one more electrochemical cell. These cells are connected in parallel, series, or both in a battery to achieve the desired capacity or output voltage.

Usually, batteries are used to power up small electric devices, e.g., flashlights, remotes, laptops, mobile devices, and more. The term “battery” is used historically to refer to a combination of multiple electrochemical cells. However, nowadays, a device with a single electrochemical cell is also known as a battery.

Brief history

The world’s first battery was introduced by Alessandro Volta - an Italian scientist - in 1800. These days, this battery is known as a voltaic pile.

Considering the limitation of voltage drop in a voltaic pile, John Fredric Daniel introduced a Daniel Cell in 1836. This cell provided more consistent and stable voltage compared to the voltaic pile.

Later in the 20th century, lead-acid and alkaline batteries were introduced. They were more dependable than all the previous ones.

Importance in modern technology

In modern technology, batteries have proven to be an excellent power backup source during a power outage. Nowadays, frequently used appliances are connected to batteries so that they can be used even if there is a power outage.

What are the main battery components?

A battery is usually made up of three main components: anode, cathode, and electrolyte. Let’s further explore these components to understand their functions.

1. Anode

It is the negative side of the battery from where the electrons come out. It indicates that the conventional current flows into a battery’s anode. Anodes are mostly a conductor, e.g., metal. Simply put, when a battery is discharged, the anode loses electrons, and this process is known as oxidation.

2. Cathode

It is marked with a positive (+) sign on the battery. It is also known as a positive electrical conductor. This is where the reduction process takes place. This component gains electrons when the discharge occurs. With cathode, you can determine the chemistry of a battery. There are different types of cathodes, such as NiMH, lithium-ion, and alkaline.

3. Electrolyte

This component of the battery is responsible for the flow of ions between cathode and anode. The electrolyte can be a gel, a liquid, or a solid. Considering the type of cathode, the type of electrolyte is changed. The ions that an electrolyte carries initiate electrochemical reactions. If you have a lithium-ion battery, remember, a gel or a liquid is used as electrolyte in such batteries.

Other components

Some other components a battery can have include a separator, a collector, and terminals. A porous material designed not to allow anode and cathode contact directly is called a separator. Being a conductor, a collector allows electrons to flow between the circuit and the electrode. Whereas the terminals connect a battery with the external circuit.

How do batteries work?

Now that you know what a battery is and its key components. It is time to explore how it actually works to provide us with an unmatched backup power source.

The two metals - cathode and anode - are attached to the opposite ends of a battery. A chemical reaction occurs between these metals and the electrolyte. As a result, one metal releases more electrons than the other one.

When electrons are released, a positive charge is developed on the metal that receives more electrons. Then, a negative charge is developed on the other side of the battery. When you connect an external circuit with the battery, electrons flow through the circuit and produce electric current.

When the current flows through the circuit, it powers up the attached load. For instance, if you attach a small light to the circuit, it will turn on when the current passes through it.

Do you know the chemical reaction in the battery is reversible? It means when you recharge a battery, it stores the chemical energy for later use. This is how a battery converts the chemical energy into electrical energy to power up different appliances.

Types of batteries

Generally, batteries are divided into two main categories: primary and secondary. Let’s get into the detailed specifics of both types of batteries.

1. Primary batteries

These types of batteries are developed for one-time use only. Once they are discharged, you can not charge them again, which is why they are also called non-rechargeable or disposable batteries. Once the energy of a primary battery is depleted, you will have to replace it.

A primary battery comes with one or more cells that create electrical energy from stored chemical energy. As soon as the chemical reactants are consumed, the battery becomes inactive.

If we talk about the shelf-life of primary batteries, they have a longer lifespan than the secondary batteries. In addition, a primary battery does not need any sort of maintenance.

Common examples: Lithium batteries, zinc-carbon batteries, and alkaline batteries are the most common examples of primary batteries. They are commonly used in portable devices, such as flashlights, clocks, watches, and toys.

2. Secondary batteries

These batteries are introduced for repetitive applications. Therefore, they are also known as accumulators or rechargeable batteries. These batteries are assembled in the discharged state. Once a secondary battery is discharged, you can simply apply electric current to charge it as many times as you need. Doing this will help the battery turn to its original state again.

A secondary battery is more sustainable and budget-friendly, as you can use it multiple times to store and reuse energy. The process of charging and discharging does not affect the voltage level. In addition, the energy density of secondary batteries is higher than that of primary batteries. It clearly indicates that a secondary battery can store a higher amount of energy per unit volume or weight.

Common examples: Nickel-metal hydride batteries, lithium-ion batteries, and lead-acid batteries are the most common examples of secondary batteries. They are usually used in grid storage, renewable energy systems, and electric vehicles.

Battery terminology

The strength of a battery can be measured by different terminologies, such as voltage, current, power, capacity, and energy density. Let’s look at what each terminology means.

1. Voltage

The voltage pushes electrons through the battery’s cell. You can also call it an electrical potential. It highly depends on the potential difference between the reactions occurring at both electrodes (anode and cathode). Simply put, the name of how strongly a cathode pulls electrons from an anode is voltage. It is measured in volts (V).

2. Current

The number of electrons that pass through a specific point of the circuit at the given time is commonly called current. It is measured in amperes (A). The higher current of the battery indicates that it can work for a longer period of time at the same voltage.

3. Power

It is the name of the voltage times current of the battery. More power means a battery can do work quickly. The power of a battery depends on both current and voltage, which shows the importance of both terminologies in helping the battery perform its functions seamlessly. The power is measured in watts (W).

4. Capacity

You can understand the capacity of a battery as the length of time for which it can provide power to the external circuit or appliances. A battery with a higher capacity can provide power for a longer period compared to a battery with a lower capacity. The capacity is measured in milliamp-hours (mAh) or watt-hours (Wh).

5. Energy density

The amount of energy batteries contain compared to their size or weight is known as their energy density. Batteries with higher energy densities can store more power in lighter or smaller packages. They become more practical for a range of applications where weight and space matter. The energy density of a battery is measured in watt-hours per kilogram (Wh/kg).

Usages of battery

Some common real-life applications of batteries include earbuds, laptops, watches, wall clocks, weighing scales, medical equipment, and domestic and commercial appliances. Let’s look at the applications of batteries when they are connected in series and parallel.

When two or more batteries are connected in series, the overall capacity remains the same, whereas the voltage is increased. For example, if you add two 12V 30Ah batteries in series, the overall circuit will have 24V 30Ah capacity.

As far as the application of batteries connected in series is concerned, look at the flashlights where multiple batteries are connected to provide the light with an enhanced voltage.

When you connect multiple batteries in parallel, it will increase the overall amp-hour capacity, whereas the voltage will remain the same. For example, if you connect two 12V 26Ah batteries in parallel, you will get a system of 12V 52Ah.

Certain camping lanterns and alarm clocks come with batteries connected in parallel. In this case, if one battery fails to perform its functions, the other will keep the operations going but will run for less time.

Conclusion

A device that comes with the ability to convert chemical energy into electrical energy is called a battery. To further understand the battery definition, read the discussion above. A battery is made up of three main components, including anode, cathode, and electrolyte. Anode and cathode are metals whereas an electrolyte can be solid, gel, or liquid.

Primary and secondary batteries are the two major types of batteries available these days. This article has also listed the battery terminologies and real-life applications you should be familiar with. In addition, the working principle of batteries is also part of this read. If you want to buy long-lasting batteries and are searching for a trustworthy seller, look no further than Renogy.

FAQs

Q: What is the difference between a battery and a cell?

A: A combination of two or more cells is called a battery. In other words, the combination of different cells connected in series, parallel, or both forms a battery. Nowadays, the device with a single cell is also referred to as the battery.

Q: How long do different types of batteries typically last?

A: Well, single use (non-rechargeable) batteries can last anywhere between 3 and 12 years, depending on their quality. On the other hand, rechargeable (secondary) batteries can last up to 6 months to 1 year.

Q: What is the difference between primary batteries and secondary batteries?

A: The primary batteries are designed for one-time use only. You can not recharge them once their energy is depleted. In comparison, you can use secondary batteries multiple times. If they are discharged, you can supply them an electric current for recharging. Once recharged, they turn back to their original state and can be reused.