When connected to an external load, a redox reaction within the battery converts high-energy reactants into lower-energy products. This releases the energy difference to the external circuit as electrical energy. Initially, “battery” referred to a device of multiple cells.
An electric battery is an energy storage device comprising one or more electrochemical cells. These cells have external connections used to power electrical devices. When providing power, the battery’s positive terminal serves as the cathode, while the negative terminal functions as the anode.
Batteries can be used to power portable devices. They let devices use electricity without the need to be plugged into main electricity sources, such as wall sockets. Mobile phones, tablets, the TV remote and torches all use batteries. Some batteries are rechargeable so they can be used again and again.
These cells have external connections used to power electrical devices. When providing power, the battery’s positive terminal serves as the cathode, while the negative terminal functions as the anode. Electrons flow through an external electric circuit to the positive terminal from the negative terminal.
Electric battery construction involves several key components that work together to store and deliver electrical energy. Anode (Negative Electrode): The anode is where the oxidation reaction occurs during discharge, releasing electrons into the external circuit. Common anode materials include graphite and lithium compounds in lithium-ion batteries.
Batteries and similar devices accept, store, and release electricity on demand. Batteries use chemistry, in the form of chemical potential, to store energy, just like many other everyday energy sources. For example, logs and oxygen both store energy in their chemical bonds until burning converts some of that chemical energy to heat.