9.3 Types of Batteries
Alkaline batteries aren’t the only type of battery still in use today. Wet cells have survived and are still used as car batteries. However, the majority of the electronic devices that have become popular in the last few decades rely on batteries that can not only hold a charge, but be recharged when they run out of power. While alkaline batteries must be thrown out when they run out of energy, rechargeable batteries, also called secondary cells, use reversible chemical reactions to regain energy after they’re completely discharged. When you charge a cell phone, laptop, or tablet computer, you’re actually reversing the chemical reaction that provides power to your device when it’s not plugged in.
Most electronic devices such as phones and laptops are powered by a lithium-ion (Li-ion) battery. Even though they now power millions of devices around the world, they’re a very new technology. The first Li-ion batteries were sold by Sony in 1991, but they’re now so common that many people own two or three devices that are powered by one.