Power-packed—but enough to run a fleet of cars or store solar energy for a rainy day?
The battery is a relatively simple device. Its powers rest on the differing ability of metals to attract and hold electrons. If two different metals are placed in a conducting liquid, called an “electrolyte,” ions with extra electrons will accumulate on one “electrode” while ions short of electrons will gravitate toward the other. You can confirm this phenomenon by placing a dime and a penny on your tongue. The moisture acts as an electrolyte, producing a weak flow of electricity (and a slightly unpleasant sensation). In a lead-acid battery, the maldistribution of electrons is powerful enough to turn over your car engine.
Such ideas are simple enough to us. But they represent a long chain of discovery stretching back to the 18th century—or perhaps to Roman-era Parthians, who had mysterious metal-lined jars that archaeologists call “Baghdad batteries.” The history of the battery is a fascinating tale, filled with memorable minds and bold experiments. “As long as the science is sound,” Henry Schlesinger writes in “The Battery,” “let the stories begin.
Unfortunately, Mr. Schlesinger becomes so absorbed in his dramatic storytelling that he almost forgets to ask some questions that contemporary readers might find most interesting. For instance: Can batteries be built big enough to store useful amounts of wind- and solar-generated electricity? Can batteries run a fleet of electric cars? Although he hints at answers, he concentrates mostly on the past.
The term “battery” was first coined in the 18th century by Daniel Gralath, a German physicist, to describe a military-like formation of so-called Leyden Jars, an early device for capturing and storing static electricity. Soon after, Benjamin Franklin “brought the lightning down from the skies” by showing that thunderbolts were composed of the same mysterious substance that those Leyden Jars had collected.
Then, in 1786, Luigi Galvani, an Italian biologist, accidentally touched a steel knife to a brass hook while dissecting a frog. The flow of electricity caused the frog’s leg to move. Galvani surmised that muscles were set into motion by something he called “animal electricity.” His discovery galvanized, so to speak, the search for a more reliable and steady source of current. In 1800, Alessandro Volta, another Italian researcher, invented one by stacking thin layers of zinc and copper, each separated by cardboard soaked in brine. The “Voltaic pile” was the first electric battery and made Volta an international celebrity. Combined with Galvani’s discoveries, it led to popular sideshows in which Voltaic juice caused corpses to move and severed heads to grimace.
Despite the battery’s seeming potential, it remained little more than a novelty and a tool for scientific experiment until Samuel Morse, an American painter, realized that it could be used to transmit messages. In the mid-1840s, Morse persuaded Congress to grant him $30,000 to string a wire from the U.S. Supreme Court building in Washington to Baltimore, carrying the world’s first telegraph message: “What Hath God Wrought?” By 1850 private investors had stretched 12,000 miles of telegraph lines across the nation, and in 1860 a coast-to-coast wire replaced the Pony Express. The power needed to send Morse Code was so small that it required only a 12-volt battery. In 1867, Lord Kelvin demonstrated the efficiency of the first transatlantic cable when he transmitted a message from London to New York by dipping two wires into a thimbleful of acid electrolyte. The stock ticker, introduced the same year, also ran on only a few volts.
By the time electric lighting arrived in the 1880s, however, it was obvious that batteries could no longer carry the load. Thomas Edison tried installing batteries in people’s houses, but the power simply wasn’t there. The future belonged to central generating stations, which converted coal or falling water into electricity. Batteries, meanwhile, were relegated to running small appliances, such as flashlights and ham radios.
A revived interest in batteries has come with the invention of portable electronic devices and their need for a miniature power supply. By the 1990s, wafer-thin lithium-ion batteries had three times the capacity of their alkaline and nickel-cadmium predecessors. As Mr. Schlesinger notes: “They seemed a perfect match for the new portability that very rapidly evolved from the AA-powered Walkman to laptops, cell phones, iPods and PDAs. . . . Although they generally don’t last beyond three years, neither do most of the products they power.”
Yet Mr. Schlesinger never asks whether lithium-ion batteries—or any other variety—can be scaled up to the point where they can power electric cars. The all-electric Nissan Leaf car, for example—due out this year—will feature a 500-pound block of lithium-ion batteries that adds $10,000 to its price yet gives it a range of only 100 miles before requiring eight hours of recharging.
Similar limitations affect commercial electrical storage. People often wonder why we can’t just build warehouses of batteries to store solar or wind-generated electricity for the days when the wind doesn’t blow or the sun doesn’t shine. But it would take 400 Leaf batteries to store 10 megawatt-hours of electricity—enough to power a small town overnight. If batteries last only three years, the costs soon become prohibitive.
Are there any breakthroughs on the horizon? “According to some experts,” Mr. Schlesinger writes, the battery industry is “close to the end of the line of usable materials.” There is some talk of “liquid metal” batteries that may open new paths of progress. Nissan claims that its Leaf batteries will be twice as powerful within a decade, but that may be wishful thinking. Batteries have come a long way in 200 years, as Mr. Schlesinger’s chronicle vividly shows. But it would be a mistake to think that we are poised on the verge of another big breakthrough just because we desperately need one.
Mr. Tucker is the author of “Terrestrial Energy: How Nuclear Power Will Lead the Green Revolution and End America’s Energy Odyssey.”
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