49 Fun Facts About Batteries

Which Samsung phone was recalled and scrapped in 2016 after its lithium-ion batteries began catching fire?

The Galaxy Note 7 kept catching fire even after Samsung swapped the first batch for handsets it had declared safe, so production ended about two months after launch and many airlines banned the phone from flights.

Which two metals did Volta stack, separated by brine-soaked paper, in his original pile?

Copper and zinc discs each add only a little voltage per pair, which is why Volta piled them high: the taller the stack, the stronger the shock it gave.

Who is credited with first using the word 'battery' for electrical apparatus, borrowing the military term for a row of guns?

Benjamin Franklin linked a set of glass capacitors to charge and fire together and named it after an artillery battery; the name stuck, though his apparatus only stored electricity and generated none.

Whose experiments on frogs' legs in the 1780s sparked the argument that led Volta to his invention?

Luigi Galvani believed the twitching came from 'animal electricity' inside the frog; Volta argued that the two metals touching it made the current, and built his pile to prove it.

While a battery is supplying power, electrons leave it through the negative terminal, which is known as what?

The anode is the electrode that gives up electrons, which makes it the negative end of a battery in use; makers mark the opposite end, the cathode, with the familiar plus sign.

What is the term for a single-use battery whose electrode materials are irreversibly changed during discharge?

Primary cells drain themselves far more slowly than older rechargeables, so an alkaline battery can lie in a drawer for years and still work the moment it is needed.

What is the approximate nominal voltage of both alkaline and zinc-carbon cells?

1.5 volts is set by the zinc and manganese dioxide reaction rather than by the size of the cell, so AAA, AA, C and D batteries all deliver it and differ only in how long they last.

Which oil giant funded the 1970s research in which Stanley Whittingham built the first working lithium battery?

Exxon, fearing the oil would run out, hired leading researchers and let them study anything except petroleum; it dropped Whittingham's battery when the oil price collapsed in the early 1980s.

Who invented lead-acid batteries in 1859, the first kind that could be recharged by reversing the current?

Gaston Planté rolled two lead sheets into a spiral in acid and found that passing current back through them restored the charge; batteries built on the same reaction are still in wide use today.

What gas does a lead-acid battery give off during overcharging, which is why it needs ventilation?

Hydrogen bubbles off, along with oxygen, when overcharging splits the water in the acid; the mixture is explosive, so one spark near the vents can blow the casing apart.

William Grove, whose 1839 nitric-acid cell powered early American telegraphs, is better remembered as a pioneer of which technology?

The fuel cell grew from Grove's 'gas battery', which made electricity by combining two gases into water; the idea then lay almost unused until the space programme took it up in the 1960s.

Which French engineer's 1860s zinc-manganese dioxide cell led to the modern dry cell?

Georges Leclanché's cell was an instant hit for telegraphs and electric bells, but it tired quickly: on early telephones a long call could drain it until the voices faded.

What did Carl Gassner mix into the ammonium chloride electrolyte to turn it into a paste for his 1886 dry cell?

Plaster of Paris bound the liquid into a paste, and Gassner sealed it inside a metal can that doubled as an electrode, the same basic layout as today's zinc-carbon batteries.

National Carbon, which sold the first mass-market dry cell in 1896, later adopted which brand name after a 1914 merger?

Eveready was shortened from the American Ever Ready Company, which National Carbon absorbed in 1914; its founder stayed on as president and the name went onto National Carbon's batteries.

Which type of rechargeable battery did Sweden's Waldemar Jungner invent in 1899?

Nickel-cadmium relied on costly cadmium, so Jungner also tried iron in its place but gave up on it, leaving Thomas Edison to develop nickel-iron two years later.

Which decrease in capacity can NiCd cells show if repeatedly recharged in the same pattern?

Memory effect got its name from an aerospace NiCd battery that computers drained to exactly the same point on every cycle; the cells then behaved as if the unused capacity had been forgotten.

What electrolyte gives the alkaline battery its name?

Potassium hydroxide is a strong alkali, where zinc-carbon cells use an acidic electrolyte; when an old battery leaks, it reacts with carbon dioxide in the air to form the feathery white crust.

Lewis Urry sold his bosses on the alkaline battery in the 1950s by racing a pair of what around the canteen?

Toy cars made the case: the one carrying Urry's new alkaline cell kept running long after its rival with an ordinary battery had stopped, and his managers were won over.

Which Japanese electronics company put the first commercial lithium-ion battery on sale in 1991?

Sony built its battery on a design by Asahi Kasei's Akira Yoshino, and the effect was a revolution in electronics: mobile phones shrank and computers became truly portable.

Which cathode material did John Goodenough introduce in 1980, the key to later commercial cells?

Lithium cobalt oxide almost doubled the voltage of Whittingham's earlier cell, to about four volts; his university declined to patent it, so Goodenough earned no royalties from the batteries it made possible.

Whittingham, Goodenough and Yoshino shared which 2019 Nobel Prize for developing the lithium-ion battery?

Chemistry was the category, and the committee's verdict was that the three had 'created a rechargeable world', putting the same battery in everything from mobile phones to laptops.

Which Boeing airliner was grounded worldwide in 2013 after its lithium-ion batteries overheated and caught fire?

The 787 Dreamliner's entire fleet of 50 was grounded after a battery burned on a parked jet in Boston and another failed in flight over Japan nine days later, forcing an emergency landing.

What process, in which lithium ions slip reversibly into a host like graphite, underlies the lithium-ion battery?

Intercalation leaves the host's structure intact as the ions slide in and out, which is why the cell survives charge after charge; Whittingham pioneered it during the 1970s oil crisis.

What speeds up the slow loss of charge in a battery sitting unused on a shelf?

Heat speeds up self-discharge, the slow chemical reactions that drain a cell with nothing connected, so a battery left in a hot car fades faster than one kept somewhere cool.

Sulphation, which ruins car batteries left flat for too long, is the build-up of hard crystals of which compound?

Lead sulphate forms on the plates every time the battery discharges and normally dissolves on recharging; left flat for weeks, the soft deposit hardens into crystals that no charger can shift.

What does the initialism SLI stand for on a car battery?

Starting, lighting, ignition batteries are built for one brief, huge burst to crank the engine, after which the alternator tops them up, so they are only ever slightly discharged.

Wilhelm König suggested the ancient 'Baghdad Battery', a clay jar holding a copper tube and an iron rod, was used for what?

Electroplating gold onto silver was König's guess, but no electroplated object from the period has ever been found, and archaeologists think such jars more likely held sacred scrolls.

Duracell's name is a shortened form of which phrase?

'Durable cell' was shortened into a brand name in the 1960s by a company that had built its reputation making long-life batteries for the military.

Which conglomerate took over Duracell in 2016 by handing back its Procter & Gamble shares in exchange?

Berkshire Hathaway paid no cash: Warren Buffett's firm handed back about $4.7 billion of P&G stock and received the whole battery business in return.

The firm that became Duracell made its name in the Second World War supplying the US military with which type of battery?

Mercury cells, devised by Samuel Ruben in 1942 at the army's request, held a steady voltage for years on the shelf and went into walkie-talkies and metal detectors; their toxicity later got them banned in many countries.

In 1980 the Eveready Battery Company renamed its alkaline power cell to what?

Energizer's drum-beating pink bunny arrived later that decade as a parody of the bunny in rival Duracell's adverts, which had been drumming on television since 1973.

Why does Duracell coat some of its coin-sized button cells?

To deter children from swallowing them, the coating is intensely bitter; the stakes are high, because a coin cell stuck in the throat can burn through tissue in as little as two hours.

What did William Nicholson and Anthony Carlisle discover with a voltaic pile in 1800?

The electrolysis of water followed within weeks of Volta announcing his pile: the two Englishmen built their own, dipped its wires in water and watched it split into its two gases.

Which ruler was so impressed by a demonstration of Volta's battery that he made him a count?

Napoleon Bonaparte joined in the experiments himself, drawing sparks from the pile and melting a steel wire, then rewarded Volta with a gold medal, a pension and the title of count.

Which flammable gas did Volta discover bubbling from the mud of Lake Maggiore in 1776?

Methane bubbled up when Volta stirred the mud of the lake bed; he bottled it, found it highly combustible and built a spark-fired 'pistol' to explode it safely in a closed vessel.

In old valve radios, which battery heated the tube filaments?

The 'A' battery made the filaments glow and give off electrons, and the 'B' put a far higher voltage on the plates to pull them across the tube, which is why a set needed both; the 'A' was often a rechargeable lead-acid battery.

Which company built South Australia's Hornsdale battery, the world's largest lithium-ion battery when it opened in 2017?

Tesla's Elon Musk had bet that the battery would be finished within 100 days of signing the contract or be free; it was switched on in December 2017 with the deadline beaten.

Below about what capacity are EV batteries typically retired to second-life uses like storing solar power?

80 percent is the usual cut-off: a pack that faded is judged too weak for a car, yet it still holds plenty for a second job such as backup power or storing a solar farm's output.

An experimental electric bell at which university has been ringing almost continuously since 1840 on its original batteries?

Oxford's bell draws so little current that its two 'dry pile' batteries have powered about ten billion rings, and to this day nobody knows exactly what the piles are made of.

To turn a lemon into a working battery, what must you push into the fruit?

Two different metals are essential, because the current comes from one of them slowly dissolving in the acid; the juice only carries charge between them, so the energy never comes from the fruit itself.

The dry cell made possible which invention, which first appeared around 1899?

The flashlight is said to owe its name to those early cells, which tired so fast that the lamp could only be flashed on briefly before the battery needed a rest.

Which physicist showed that the corrosion in Volta's battery was unavoidable, not the mere nuisance Volta believed?

Michael Faraday proved that the current a cell delivers is matched exactly by the metal it consumes, so the corrosion Volta hoped to engineer away is the very thing that powers a battery.

What improvement did Camille Faure make to the early rechargeable battery around 1880?

Plates pasted with lead oxide could be stacked for more power and were far easier to mass-produce than rolled metal sheets, which turned the rechargeable battery into a factory product.

What is the main advantage of a dry cell's paste electrolyte over a wet cell's liquid one?

No spills at any angle, because the paste holds no free liquid, so batteries could leave their fragile upright glass jars and go into things people carry.

Which chemist used a giant battery at London's Royal Institution to isolate sodium, calcium and other elements for the first time?

Humphry Davy ran current through molten compounds and watched new metals appear at the wire; the same battery also fed his arc lamp, the first electric light, decades before the bulb.

Whose 1836 cell served as the first working standard for defining the volt?

Daniell's two-liquid cell stopped gas bubbles from smothering the electrode, so it gave a far steadier current than Volta's pile, and that reliability made it the telegraph engineers' yardstick.

Sakizō Yai's early Japanese dry battery powered a seismograph shown at an 1893 world's fair in which city?

Chicago's World's Columbian Exposition showed the instrument; a year later Japan's army took the cells to war with China, because the liquid in ordinary batteries froze in the cold and Yai's kept working.

Thomas Edison hoped his 1901 nickel-iron battery would make which technology the standard?

Electric cars were the prize, but Edison's first cells leaked and barely beat lead-acid; by the time his improved battery was ready seven years later, Ford's cheap petrol Model T had taken the market.

Which 1860s battery, named for the way its two liquids stay separated, became a favourite of American and British telegraph lines?

The gravity battery needs no porous barrier: the denser of its two solutions simply sits beneath the lighter one, which lowers the resistance and gives a stronger current.