Li-ion batteries are mainly used in devices such as power tools, and handheld devices owing to their high energy density and rechargeable properties. There are several types of power tools such as engine-driven power, electric power, and pneumatic power tools. Electric power tools works on both electric and battery source of power. Currently, most companies are manufacturing power tools that operate on Li-ion batteries as it provides high power capability despite its compact size and reduces the overall weight of power tool. Power tools are can be used for various purposes such as screw driving, drilling, chiseling, shaping, routing, sanding, buffing, polishing, and leveling.