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Chemical reactions are the transformations that lead to the conversion of one or more substances into different substances with distinct properties.
During a chemical reaction, the bonds between atoms are broken and new bonds form, leading to the creation of new compounds. This process can either absorb energy (endothermic) or release energy (exothermic).

Distinguishing Reactions

In the case of electrolysis, the chemical reaction is non-spontaneous, meaning it does not occur on its own and requires external energy, typically in the form of an electric current, to proceed. Conversely, the reactions in a battery are spontaneous; they occur naturally and produce electrical energy without the need for an external power source.

• Non-spontaneous reactions: These need an input of energy, like in electrolysis where electricity is used to drive the reaction.
• Spontaneous reactions: These occur without external energy input, releasing energy which can be harnessed, as in a battery.

Electric current is a flow of electric charge, typically carried by moving electrons in a conductor.
In electrolysis, it is the driving force that initiates and sustains the non-spontaneous chemical reaction. When an electric current is applied to an electrolyte, it causes ions to move towards the electrodes, where they either gain or lose electrons and transform into new substances.

Electrons at Work

Positive ions, or cations, move towards the cathode where they gain electrons (reduction), and negative ions, or anions, move towards the anode where they lose electrons (oxidation). This movement and subsequent chemical changes are directly facilitated by the external electric current applied to the system.

Batteries store chemical energy and convert it into electrical energy through spontaneous chemical reactions.
This process is called electrochemical conversion. A battery consists of two different electrodes, the anode and cathode, which are separated by an electrolyte.

Creating a Current

When the battery is in use, oxidation occurs at the anode, releasing electrons that then flow through the external circuit to the cathode, which is undergoing reduction and accepts electrons. This flow of electrons is the electric current that can power devices.

Unlike electrolysis, battery operation doesn't require any external electrical input as the chemical reactions inherent to the battery materials spontaneously provide the necessary energy to generate the electric current.