Lead-acid cells and batteries

You’ve already seen the basic configuration for a lead-acid cell. This has a solution of sulfuric acid, along with a lead electrode (negative) and a lead-dioxide electrode (positive). These batteries are rechargeable.
Automotive batteries are made from sets of lead-acid cells having a free-flowing liquid acid. You cannot tip such a battery on its side, or turn it upside-down, without running the risk of having some of the acid electrolyte get out.
Lead-acid batteries are also available in a construction that uses a semisolid electrolyte. These batteries are popular in consumer electronic devices that require a moderate amount of current. Notebook or laptop computers, and portable video-cassette recorders (VCRs), are the best examples.
A large lead-acid battery, such as the kind in your car, can store several tens of ampere- hours. The smaller ones, like those in notebook computers, have less capacity but more versatility. Their overwhelming advantage is their ability to be used many times at reasonable cost.