Page 54 - Innovator's Science-8

Today, lithium-ion (Li-ion) batteries are the most widely used rechargeable
batteries and are found in almost every device that runs on batteries, such

as phones, laptops, and electric vehicles. These batteries depend on special
metals like lithium and cobalt, which are found only in a few places around
the world. Because of this, many countries are working to secure enough
supply, recycle used batteries, and create better battery technologies.

Scientists are also developing solid-state batteries, which use solid
materials instead of liquid or paste electrolytes. These new batteries would
be safer, charge faster, and last longer. Advancing rechargeable battery
technology is crucial as the world shifts toward cleaner and more

sustainable energy solutions.

Know Your Scientist
Dr. Michael Faraday (1791-1867) was one of the greatest experimental scientists of all time. Born in London to
a poor family, he had very little formal education but an unshakable curiosity about nature. His experiments
with electricity and magnetism led to the discovery of electromagnetic induction - the process by which
electricity can be generated from magnetism. This discovery became the basis of electric generators and
transformers. Faraday's life reminds us that true learning begins with curiosity and that great discoveries often
come from simple observations.

Grasp-Up

Electric Current: The flow of electrons through a conductor.
Circuit: A complete path that allows electric current to flow.
Conductor: A material that allows electric current to pass through it easily.
Insulator: A material that does not allow electric current to pass through it.
Filament: A thin wire inside a bulb that glows when current passes through it.
Electromagnet: A temporary magnet formed when electric current flows through a coil of wire.
Electric Bell: A device that works on the magne c effect of electric current.
Cell: A device that converts chemical energy into electrical energy.
Ba ery: A group of cells connected together to provide electric power.
Rechargeable Ba ery: A ba ery that can be used again a er charging.

Points to Reflect

• Electricity plays an important role in lighting, heating, and running machines.
• Electric current flows only through a closed circuit.
• The direction of conventional current is opposite to the flow of electrons.
• Electric current produces heating and magnetic effects.
• The heating effect is used in devices such as electric bulbs, heaters, and toasters.
• The magnetic effect is used in electromagnets, electric bells, and motors.
• The strength of an electromagnet depends on the number of turns in the coil and the amount of current.
• Cells and batteries convert chemical energy into electrical energy.
• Rechargeable batteries can be used many times after charging.

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Science-8