Chapter 3
Raw Power » A Tall Glass of Juice

tir up some copper and zinc to make your own 1-volt liquid battery. People used to make a lot of things at home. They churned their own butter, cooked food without microwaves, and knitted pairs of socks. Some hundred years ago, people even made their own electricity: DIY batteries powered their doorbells and telegraphs.

Today, batteries meant for heavy use are rechargeable. But how do you get power when there is no grid? Early batteries were designed to be "renewed," which meant replacing or replenishing their chemicals to give them new energy.