Technologies

Phone Plugged in 24/7? Experts Reveal the Science Behind Battery Damage

Phone batteries degrade over time, but heat and use habits are a larger danger than keeping your phone plugged in.

There was a time when smartphone users were warned not to leave their phones plugged in for too long, or it could do damage to the battery. While modern smartphones now have overcharge protection that keeps them safe, many people still have questions about whether keeping their phone perpetually plugged in will damage the battery.

The short answer is no. Keeping your phone plugged in all the time won’t ruin your battery. Modern smartphones are built with smart charging systems that cut off or taper power once they’re full, preventing the kind of «overcharging damage» that was common in older devices. So if you’re leaving your iPhone or Android on the charger overnight, you can relax.

That said, «won’t ruin your battery» doesn’t mean it has no effect. Batteries naturally degrade with age and use, and how you charge plays a role in how fast that happens. Keeping a phone perpetually at 100% can add extra stress on the battery, especially when paired with heat, which is the real enemy of longevity.

Understanding when this matters (and when it doesn’t) can help you make small changes to extend your phone’s lifespan.

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The science behind battery wear

Battery health isn’t just about how many times you charge your phone. It’s about how it manages voltage, temperature and maintenance. Lithium-ion batteries age fastest when they’re exposed to extreme levels: 0% and 100%.

Keeping them near full charge for long stretches puts additional voltage stress on the cathode and electrolyte. That’s why many devices use «trickle charging» or temporarily pause at 100%, topping up only when needed.

Still, the biggest threat isn’t overcharging — it’s heat. When your phone is plugged in and running demanding apps, it produces heat that accelerates chemical wear inside the battery. If you’re gaming, streaming or charging on a hot day, that extra warmth does far more harm than leaving the cable plugged in overnight.

Apple’s take

Apple’s battery guide describes lithium-ion batteries as «consumable components» that naturally lose capacity over time. To slow that decline, iPhones use Optimized Battery Charging, which learns your daily routine and pauses charging at about 80% until just before you typically unplug, reducing time spent at high voltage.

Apple also advises keeping devices between 0 to 35 degrees Celsius (32 to 95 degrees Fahrenheit) and removing certain cases while charging to improve heat dissipation. You can read more on Apple’s official battery support page.

What Samsung (and other Android makers) do

Samsung offers a similar feature called Battery Protect, found in One UI’s battery and device care settings. When enabled, it caps charging at 85%, which helps reduce stress during long charging sessions.

Other Android makers like Google, OnePlus and Xiaomi include comparable options — often called Adaptive Charging, Optimized Charging or Battery Care — that dynamically slow power delivery or limit charge based on your habits. These systems make it safe to leave your phone plugged in for extended periods without fear of overcharging.

When constant charging can hurt

Even with these safeguards, some conditions can accelerate battery wear. As mentioned before, the most common culprit is high temperature. Even for a short period of time, leaving your phone charging in direct sunlight, in a car or under a pillow can push temperatures into unsafe zones.

Heavy use while charging, like gaming or 4K video editing, can also cause temperature spikes that degrade the battery faster. And cheap, uncertified cables or adapters may deliver unstable current that stresses cells. If your battery is already several years old, it’s naturally more sensitive to this kind of strain.

How to charge smarter

You don’t need to overhaul your habits but a few tweaks can help your battery age gracefully.

Start by turning on your phone’s built-in optimization tools: Optimized Battery Charging on iPhones, Battery Protect on Samsung devices and Adaptive Charging on Google Pixels. These systems learn your routine and adjust charging speed so your phone isn’t sitting at 100% all night.

Keep your phone cool while charging. According to Apple, phone batteries perform best between 62 and 72 degrees Fahrenheit (16 to 22 degrees Celsius). If your phone feels hot, remove its case or move it to a better-ventilated or shaded spot. Avoid tossing it under a pillow or too close to other electronics, like your laptop, and skip wireless chargers that trap heat overnight.

Use quality chargers and cables from your phone’s manufacturer or trusted brands. Those cheap «fast-charge» kits you find online often deliver inconsistent current, which can cause long-term issues.

Finally, don’t obsess over topping off. It’s perfectly fine to plug in your phone during the day for short bursts. Lithium-ion batteries actually prefer frequent, shallow charges rather than deep, full cycles. You don’t need to keep it between 20% and 80% all the time, but just avoid extremes when possible.

The bottom line

Keeping your phone plugged in overnight or on your desk all day won’t destroy its battery. That’s a leftover myth from a different era of tech. Modern phones are smart enough to protect themselves, and features like Optimized Battery Charging or Battery Protect do most of the heavy lifting for you.

Still, no battery lasts forever. The best way to slow the inevitable is to manage heat, use quality chargers and let your phone’s software do its job. Think of it less as «babying» your battery and more as charging with intention. A few mindful habits today can keep your phone running strong for years.

Technologies

Today’s NYT Mini Crossword Answers for Wednesday, Jan. 28

Here are the answers for The New York Times Mini Crossword for Jan. 28.

Looking for the most recent Mini Crossword answer? Click here for today’s Mini Crossword hints, as well as our daily answers and hints for The New York Times Wordle, Strands, Connections and Connections: Sports Edition puzzles.

Need some help with today’s Mini Crossword? Read on for all the answers. And if you could use some hints and guidance for daily solving, check out our Mini Crossword tips.

If you’re looking for today’s Wordle, Connections, Connections: Sports Edition and Strands answers, you can visit CNET’s NYT puzzle hints page.

Read more: Tips and Tricks for Solving The New York Times Mini Crossword

Let’s get to those Mini Crossword clues and answers.

Mini across clues and answers

1A clue: Remove from a position of power
Answer: OUST

5A clue: Not cool
Answer: UNHIP

7A clue: «Fine, see if ___!»
Answer: ICARE

8A clue: Kind of bored
Answer: JADED

9A clue: Primatologist’s subjects
Answer: APES

Mini down clues and answers

1D clue: Kind of board
Answer: OUIJA

2D clue: Prepare to use, as a pen
Answer: UNCAP

3D clue: Desirable place to sit on a hot day
Answer: SHADE

4D clue: Pair on a bicycle
Answer: TIRES

6D clue: ___ Xing (street sign)
Answer: PED

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Technologies

Today’s NYT Connections: Sports Edition Hints and Answers for Jan. 28, #492

Here are hints and the answers for the NYT Connections: Sports Edition puzzle for Jan. 28, No. 492.

Looking for the most recent regular Connections answers? Click here for today’s Connections hints, as well as our daily answers and hints for The New York Times Mini Crossword, Wordle and Strands puzzles.

Today’s Connections: Sports Edition is a tough one. If you’re struggling with today’s puzzle but still want to solve it, read on for hints and the answers.

Connections: Sports Edition is published by The Athletic, the subscription-based sports journalism site owned by The Times. It doesn’t appear in the NYT Games app, but it does in The Athletic’s own app. Or you can play it for free online.

Read more: NYT Connections: Sports Edition Puzzle Comes Out of Beta

Hints for today’s Connections: Sports Edition groups

Here are four hints for the groupings in today’s Connections: Sports Edition puzzle, ranked from the easiest yellow group to the tough (and sometimes bizarre) purple group.

Yellow group hint: Stats about an athlete.

Green group hint: Where to watch games.

Blue group hint: There used to be a ballpark.

Purple group hint: Names are hidden in these words.

Answers for today’s Connections: Sports Edition groups

Yellow group: Player bio information.

Green group: Sports streamers.

Blue group: Former MLB ballparks.

Purple group: Ends in a Hall of Fame QB.

Read more: Wordle Cheat Sheet: Here Are the Most Popular Letters Used in English Words

What are today’s Connections: Sports Edition answers?

The yellow words in today’s Connections

The theme is player bio information. The four answers are alma mater, height, number and position.

The green words in today’s Connections

The theme is sports streamers. The four answers are Netflix, Paramount, Peacock and Prime.

The blue words in today’s Connections

The theme is former MLB ballparks. The four answers are Ebbets, Kingdome, Three Rivers and Tiger.

The purple words in today’s Connections

The theme is ends in a Hall of Fame QB. The four answers are forewarner, Harbaugh, honeymoon and outmanning.

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Technologies

Google Rolls Out Expanded Theft Protection Features for Android Devices

The latest Android security update makes it harder for thieves to break into stolen phones, with stronger biometric requirements and smarter lockouts.

Google on Tuesday announced a significant update to its Android theft-protection arsenal, introducing new tools and settings aimed at making stolen smartphones harder for criminals to access and exploit. The updates, detailed on Google’s official security blog, build on Android’s existing protections and add both stronger defenses and more flexible user controls.

Smartphones carry your most sensitive data, from banking apps to personal photos, and losing your device to theft can quickly escalate into identity and financial fraud. To counter that threat, Google is layering multiple protective features that work before, during and after a theft.

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At the center of the update is a revamped Failed Authentication Lock. Previously introduced in Android 15, this feature now gets its own toggle in Android 16 settings, letting you decide whether your phone should automatically lock itself after repeated incorrect PIN or biometric attempts. This gives you more control over how aggressively your phone defends against brute-force guessing without weakening security.

Google is also beefing up biometric security across the platform. A feature called Identity Check, originally rolled out in earlier Android versions, has been broadened to apply to all apps and services that use Android’s Biometric Prompt — the pop-up that asks for your fingerprint or face to confirm it’s really you — including third-party banking apps and password managers. This means that even if a thief somehow bypasses your lock screen, they’ll face an additional biometric barrier before accessing sensitive apps.

On the recovery side, Google improved Remote Lock, a tool that allows you to lock a lost or stolen device from a web browser by entering a verified phone number. The company added an optional security challenge to ensure only the legitimate owner can initiate a remote lock, an important safeguard against misuse.

And finally, in a notable regional rollout, Google said it is now enabling both Theft Detection Lock and Remote Lock by default on new Android device activations in Brazil, a market where phone theft rates are comparatively high. Theft Detection Lock uses on-device AI to detect sudden movements consistent with a snatch-and-run theft, automatically locking the screen to block immediate access to data.

With stolen phones often used to access bank accounts and personal data, Google says these updates are meant to keep a single theft from turning into a much bigger problem.