Plant extracts

A rechargeable battery is technically a group of two or more secondary cells, such as a laptop battery containing six individual cells. However, they are often used to refer to a single cell, such as a NiMH AA battery. These batteries can be restored to full charge by the application of electrical energy, such as through a battery charger. In other words, they are batteries in which the electrochemical reaction that releases energy is readily rechargeable. Rechargeable batteries come in many different sizes using different chemicals. Commonly used secondary cell chemistries are lead acid, nickel cadmium (NiCd), nickel metal hydride, lithium ion, and lithium ion polymer .