What is inside of a Lithium-ion battery?

Nowadays, more and more applications are powered by Lithium-ion(Li-ion) batteries. Because of high energy density, high battery efficiency, low weight and long service life, Li-ion batteries are widely applied in diverse areas ranging from small appliances and IT devices to power tools, energy storage systems and electric vehicles.

So what's exactly inside of a Lithium-ion battery?

Lithium-ion batteries consist of largely four main components: cathode, anode, electrolyte, and separator. Every single component of a Li-ion battery is essential as it cannot function when one of the components is missing.