Batteries do two things: they store energy and they turn
chemical energy into electrical energy. The energy stored in a battery can
produce light, heat, or motion. Our cell phones, flashlights, and electronic
toys would not work without batteries. Beyond household devices, batteries today can
power huge machines like the rovers that travel around Mars. Batteries of the
future might even power self-driving cars. This book is one of a series of six books designed for 4-7 graders.