Why Do Smartphone Batteries Fail So Quickly?

It's a familiar story. You buy a new phone, and for a while the battery is good. You take your phone out in the morning, spend all day at work, and still have more than enough charge left for the journey home. But fast forward a year or so and everything's changed. You can practically see the battery meter tick down—or at least you could if you hadn't completely dimmed the screen in a futile attempt to keep your music playing just long enough to reach your front door.

Clearly, something has changed. But why is it that smartphone batteries seem fail so quickly?

In some respects, the problem is that smartphones require more power than ever thanks to more complex processors and larger screens, while batteries are getting smaller as companies push to make phones thinner. But that's a general trend. We're interested in why your specific battery doesn't work as well as it used to.

Smartphones, like many portable electronics, use Li-ion batteries because they're much lighter than other batteries and hold their charge for a long time. They work by moving Lithium ions between two electrodes – a Lithium-Cobalt Oxide cathode and a Carbon (graphite) anode. When you charge the battery the ions collect on the anode, and when you discharge it (to power a device) the ions move back to the cathode. This process is called 'cycling', and it's an accepted part of Li-ion battery design.

If the cycling process were 100% efficient, your battery would never get worse. But as you've probably guessed, it isn't. Each time you charge a battery, a film of Lithium atoms remains bonded to the anode, which reduces its capacity. If the ions can't move, they can't transfer their charge and therefore can't deliver power. The next time you charge it, another layer is deposited.

Once that process is replicated a few hundred times, you'll start to see a noticeable drop in amount of power a battery can store. An increasingly thick layer of immobile Lithium (in the form of Lithium Oxide and Lithium Carbonate) collects on the anode, obstructing interaction with the graphite.

But that's not the whole story. The inefficiencies of cycling a battery cause a constant but gradual decline in capacity. But if you think your battery's capacity has dropped off suddenly and without any obvious cause you're not necessarily imagining it.

Just as the anode can get covered with a film of material by the charging process, the cathode can also develop a similar layer because of something called electrolyte oxidation. The hotter a battery gets (or the higher its voltage), the quicker and more damaging the reaction is. The cathode's reactive abilities are immediately impeded, causing a sudden and irreversible capacity loss – one which is more immediately noticeable compared to the nature cycle of charge and discharge.

The end result is that the lithium-ion reaction used to deliver power can no longer happen properly, and the battery won't retain or deliver as much power as it did when it was new. Essentially, the reason your smartphone battery stops working is because the electrodes inside have gone rusty.

But knowing why your battery keeps dying is only half of the problem. How can you use this information to protect your phone's battery life?

One important thing to do is avoid exposing your battery to extreme temperatures. Heat above 35 degrees Celsius noticeably accelerates the cathode's decline. Battery capacity is also diminished at low temperatures, but this is (usually) a temporary effect. For ideal performance, keep your battery at a temperature between 16-22 degrees Celsius. This may mean removing any phone cases during charging and even unplugging it during charging if it gets too hot.

Speaking of charging, here's another tip: don't charge your battery to 100%. It might seem counter-intuitive, but unless you need a full charge for portability's sake the battery will fare better on a partial one. High temperatures actually damage the battery by raising the voltage, and when you charge a battery to 100% the voltage is also raised to its limits.

Unlike some rechargeables, Li-ion batteries are not negatively affected by a partial charge, so ideally you should prevent a full charge occurring unless you really will need that extra few percent. You'll stretch the battery's lifespan as far as possible if you maintain the charge between 20-80% whenever possible.

It's worth noting that you should also keep devices partially charged during storage or periods of disuse. The batteries need to retain some power to keep their internal protection circuits active, and allowing them to fully discharge (a 'deep discharge') will destroy its ability to hold charge at all. On a day-to-day basis, Li-ion batteries prevent this from happening by claiming to be empty while they still have some power left, but they can fail if they're then left to self-discharge beyond that point. If you store a device for a long period of non-use, charge it to around 50%. This keeps the voltage low (which protects the cathode) but retains enough capacity to keep the protection circuits active for potentially months.

Unfortunately, these techniques only prevent a battery from losing its efficiency. There's not much you can do to rejuvenate an aging battery without specialist equipment—but at least you can now stop yours getting any worse!

This post originally appeared on our UK site.

Stuart C. Wilson/Getty Images
How to Eat (and Drink) Like the Queen: Royal Chefs Reveal Elizabeth II's Favorite Foods
Stuart C. Wilson/Getty Images
Stuart C. Wilson/Getty Images

It’s good to be the Queen. Twice a week, Queen Elizabeth II browses a leather-bound menu of the latest meal suggestions from the royal family’s head chef, Mark Flanagan, and whichever items she checks off, she gets to eat. The Telegraph recently spoke with two former royal chefs who were ready to dish out the Queen’s most personal food tastes.

Mealtime at Buckingham Palace isn’t always the extravagant affair non-royals might assume it to be. As former personal chef to the Queen Darren McGrady told The Telegraph, her royal majesty is no foodie. “She eats to live,” he said. And even the delicacies she does enjoy don’t appear on her plate every day. “The Queen loved scrambled eggs with smoked salmon and a grating of truffle. But she was too frugal to ever order fresh truffles and only really enjoyed them at Christmas when the truffles were sent as a gift.” Instead, she prefers regular cereal like Special K with fresh fruit for a typical breakfast.

But even the most humble meals served to the Queen are held to high standards. When Owen Hodgson, who worked in the palace kitchen in the early 1990s, spoke to The Telegraph, he recalled the level of detail that went into a simple tuna fish sandwich. The crusts were removed, the bread was buttered on both sides, and the sandwiches were cut into eight identical triangles before they were fit for the Queen.

Of course, the royal diet includes the most classic of British culinary traditions, afternoon tea. Queen Elizabeth has a weakness for chocolate, and there’s usually chocolate perfection pie or chocolate biscuit cake included in the spread.

For dinner, she likes to keep things light with grilled fish like sole served with vegetables and a salad. On Sundays, she enjoys a roast, preferring the well-done end slice over something more rare. Ingredients from her farms, like white peaches from Windsor Castle and fillets of beef and venison from Sandringham and Balmoral, are often worked into the menu.

As for her preferred drink, it's a gin and Dubonnet with a slice of lemon. She also sometimes drinks wine with lunch, and reportedly enjoys a glass of champagne before bed.

In 2017, the royal palace made it a little easier to drink like the Queen when they made wine from her royal vineyard available for the public to purchase. Beyond that, you may need to hire a personal chef of your own to recreate her full experience.

[h/t The Telegraph]

9 Things You Might Not Know About Defender

by Ryan Lambie

When Defender arrived in arcades back in 1980, nothing looked or sounded quite like it. The controls had a steep learning curve, and its shooting action was intense and relentlessly difficult. Yet Defender's boldness made it stand out in arcades full of Space Invaders clones, and gamers quickly fell in love with it.

Created by a designer pushing the boundaries of early '80s technology, Defender's development wasn't without its drama. Here's a look at Defender's making and its lasting effect on the games industry.


With its foundations tracing back to the 1940s, American company Williams specialized in making pinball machines. When Pong ushered in a new age of electronic games in the 1970s, Williams knew it had to break into the same market, but its first attempt was tentative, to say the least: 1973's Paddle Ball was, for the most part, a straight replica of Pong's bat-and-ball action. Fortunately, a young programmer named Eugene Jarvis had a more pioneering spirit.


Jarvis joined Williams in the late 1970s, where he initially worked on the software for the company's pinball machines—titles included Airborne Avenger, Gorgar, and Laser Ball. But even as those machines were making their way into arcades, they were being roundly upstaged by a new game on the block—the coin-guzzling shooter, Space Invaders. The game immediately inspired Jarvis to make his own sci-fi shooter, though one which also took in the vector graphics of the seminal Spacewar (a game he'd played while in college) and a hint of chess. He wanted his game, he later told WIRED, to be a "rich, tactical and strategic experience."


As Jarvis's ideas for his game began to develop—and it moved further and further away from the straight "blast the aliens" scenario popularized by Space Invaders—he began to think about an objective that involved rescue and defense rather than straight-up shooting. And early on, he adopted the name Defender, derived from the '60s courtroom drama series, The Defenders.

"I kind of liked that show," Jarvis said in Steven Kent's book, The Ultimate History Of Video Games. "You know, if you're defending something, you're being attacked, and you can do whatever you want."


Jarvis and his small team of programmers and designers, which included Larry DeMar and Sam Dicker, worked up a game design which, for its time, was hugely ambitious. Back then, most games took place on a single, static screen. What Jarvis proposed was a game which scrolled smoothly and rapidly along a map that was far larger than the display. At the top of the screen, a small mini map showed the player's current position. Both ideas were groundbreaking, and the mini map is a ubiquitous design feature in the games of today.


As months of development passed, Jarvis was put under increasing pressure to get Defender finished in time for a trade show called the Amusement and Music Operators Association Expo. Jarvis worked feverishly to meet the deadline, but on the evening before the trade show, he had a horrifying realization: the game lacked an attract mode—the demo designed to show would-be customers how the game looks in action. An all-night coding session began, which, following another terror-inducing moment where the game refused to load up properly, the finished Defender was ready on the morning of the expo.


Defender cut a strange and unnerving figure at the AMOA trade show. Where most games of the time had a joystick and one button, Defender had a joystick and five buttons—something which, Jarvis later suggested, left some people wary of even trying it. At first, though, Jarvis wasn't concerned, saying in an interview on the Williams Arcade's Greatest Hits game disc that the team was "proud that it intimidated everyone."


Everything changed when Defender appeared in arcades. Williams's first game of the '80s was also its biggest, selling 55,000 cabinets and reportedly making more than $1 billion in revenue. Players, it seems, couldn't get enough of Defender's speed, color, and sheer challenge.


While Defender became famous for its vertical difficulty level, a certain breed of gamer rose to the challenge. The game's most dedicated players even discovered a bug: reach 990,000 points, and an error in the game's algorithm results in a sudden shower of extra lives and smart bombs. Yet even the bug added to Defender's absorbing challenge; as Jarvis told US Gamer, "Some of the richest elements of Defender [...] were bugs, things that I never even in my wildest imagination could have coded."


Defender's groundbreaking design paved the way for an entire generation of scrolling shooters, including Jarvis's 1981 sequel Stargate, Konami's Gradius series, and many more. Even today, Defender continues to inspire 21st-century game designers. Finnish developer Housemarque's side-scrolling shooter Resogun draws directly on the mechanics in Defender. In 2017, Jarvis teamed up with Housemarque to develop the game Nex Machina, which released to overwhelmingly positive reviews.

More than 30 years later, Defender's audacious design is still making an impact.


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