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Electrolytes in electricity: what they are and what they are for

Electrolytes in electricity: what they are and what they are for

Electrolytes, substances capable of conducting electricity through the dissociation of ions in aqueous solutions, play a fundamental role in the field of electricity.

Its ability to separate and mobilize electrically charged ions enables the conduction of electrical current in a variety of applications, from batteries and fuel cells to chemical processes and electrolysis.

In this article, the underlying concepts of electrolytes will be explored in detail and their importance in everyday life and the development of sustainable technologies will be discussed.

What are electrolytes?

To understand the role of electrolytes in electricity, we must first define what electrolytes are. In simple terms, electrolytes are substances that contain electrically charged ions, either positive (cations) or negative (anions). These ions are released into an aqueous solution and are capable of conducting an electrical current.

Electrolytes can be inorganic, such as sodium chloride (common salt) or sulfuric acid, or they can be organic, such as weak acids and bases.

Additionally, electrolytes can be found in a variety of forms, from liquids to gels and solids, depending on their application.

Role of electrolytes in electricity

Electrolytes play an essential role in the conduction of electricity due to their ability to separate charged ions.

When a potential difference (voltage) is applied across an electrolyte, positive and negative ions move toward opposite poles, generating an electric current. This process is called electrolysis.


Electrolytes in electricity: what they are and what they are forTo better understand this process, let's consider a common example: a battery. Batteries contain electrolytes that allow the transfer of electrons between the electrodes (anode and cathode).

Ions move through the electrolyte, releasing electrons at the cathode and accepting electrons at the anode, generating an electrical current that can be used to power electronic devices.

In water electrolysis, another notable example, an electrolyte solution of water with small amounts of salt is used to break down water into its components, hydrogen and oxygen, through the application of an electric current.

Types of Electrolytes

There are several types of electrolytes, each with specific properties and applications. Some of the most common types include:

  • Acids: contain hydrogen ions (H+) and are common in lead-acid batteries, such as those used in automobiles. The chemical reaction in these batteries involves the transfer of hydrogen ions between the anode and the cathode.

  • Alkaline: Contain hydroxyl ions (OH-) and are common in alkaline batteries, such as AAA alkaline batteries. These batteries are known for their long life and high efficiency.

  • Saline: contain positive and negative ions derived from salts dissolved in water. Sodium chloride is an example of a common salt electrolyte.

  • Solids: These are materials that can conduct ions through their solid crystalline structure. They are used in solid-state batteries and show advantages in terms of safety and energy density.

Examples of applications in electricity

Electrolytes have a wide range of applications in electricity, ranging from batteries and fuel cells to chemical processes and electrolysis.

Here are some of the most notable applications:


Batteries are one of the most common examples of the application of electrolytes in electricity.

From alkaline batteries in small devices to lithium-ion batteries in electric vehicles, electrolytes allow energy to be stored and released in a controlled manner.

Fuel cells

Fuel cells use electrolytes to generate electricity from chemical reactions, such as the oxidation of hydrogen and oxygen.

These cells are a clean and efficient energy source used in electric vehicles and stationary applications.


Electrolysis is a process that uses electrolytes to break down chemicals into their basic components by applying an electrical current. This process is used in the production of hydrogen, in the galvanization of metals and in the purification of minerals.

Electrolytic capacitors

Electrolytic capacitors use electrolytes to store electrical charges. They are common in electronic circuits and are used to smooth out voltage fluctuations and store energy in devices such as power supplies.


Electrochemistry is a branch of chemistry that studies chemical reactions involving the transfer of electrons and ions.

Electrolytes are fundamental in electrochemistry and are used in a variety of applications, such as chemical synthesis and energy research.

Electrolytes in solar energy

Electrolytes have crucial relevance in the solar energy sphere, influencing both the photovoltaic conversion of sunlight into electricity and energy storage.

Photovoltaic energy

Electrolytes in electricity: what they are and what they are forIn photovoltaic conversion, solar cells transform sunlight into electricity. Some advanced solar cells, such as perovskite cells, use electrolytes in their design to improve charge transfer and the separation of electrons and holes generated by sunlight.

This maximizes conversion efficiency and expands the potential for generating electricity from solar radiation.

Energy storage

In the field of solar energy storage, solar batteries play a vital role in overcoming the variability of sunlight availability. These batteries use electrolytes inside to facilitate the transfer of electrons during charging and discharging.

Lithium-ion batteries, common in solar storage systems, exemplify how electrolytes allow excess energy generated during the day to be stored for later use, such as at night or on cloudy days. This storage improves the efficiency and reliability of solar energy systems by ensuring a continuous supply of electricity.

Publication Date: May 13, 2015
Last Revision: October 29, 2023