Technologies
Does Charging Your Phone Overnight Damage the Battery? We Asked the Experts
Modern smartphones are protected against overcharging, but heat and use habits can still degrade your battery over time.
Plugging your phone in before you head to bed might seem like second nature. That way by the time your alarms go off in the morning, your phone has a full charge and is ready to help you conquer your day. However, over time, your battery will start to degrade. So is keeping your phone plugged in overnight doing damage to 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.
Tariffs implemented by President Donald Trump were struck down by the Supreme Court last month. Companies that were subjected to those fees, such as FedEx and Dollar General, have since sued the federal government, and Nintendo wants a piece of the action.
Nintendo filed a lawsuit against the federal government in the US Court of International Trade on Friday, as first spotted by Aftermath. The complaint seeks refunds of tariffs Nintendo paid, plus interest, and asks the court to declare the tariffs unlawful and stop the government from collecting them going forward.
«Since February 1, 2025, President Trump has executed the unlawful Executive Orders, imposing tariffs on imports from a vast swath of countries,» Nintendo said in the complaint.
When reached for comment, Nintendo of America confirmed the lawsuit.
«We can confirm that we filed a request. We have nothing else to share on this topic,» Nintendo of America said in an emailed statement on Friday, March 6.
It’s unclear how much Nintendo paid in tariffs, and it did not state an amount in the lawsuit. While the Switch 2 was priced at $450 when it launched last year, and has stayed at that amount, Nintendo did increase the price of the original Switch and accessories for both consoles. Microsoft and Sony also increased the prices of their hardware and accessories last year due to tariffs.
The White House didn’t immediately respond to a request for comment.
On Feb. 20, the Supreme Court ruled by a vote of 6 to 3 that the sweeping tariffs Trump instituted last year exceeded his executive powers. Following the ruling, on the same day, Trump announced a new set of tariffs of 10% on imported goods that would last for 150 days, starting Feb. 24.
The decision on what to do with the collected tariffs — a reported $166 billion — has been left to the US Court of International Trade. Judge Richard Eaton told the US Customs and Border Protection on Wednesday, March 4, to refund the importers that were forced to pay tariffs, which is more than 330,000. On Friday, the CBP said it couldn’t easily issue tariff refunds because its system requires duties to be recalculated and refunds processed entry by entry. This process would involve tens of millions of transactions. The agency said it’s updating its systems and could start providing refunds by late April.
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Technologies
The Apple Watch Series 12 Could Bring Back a Throwback iPhone Feature
Everything we’ve heard so far about the rumored Apple Watch Series 12.
We’re hot off a busy March Apple launch with seven new products, including an iPhone 17E, updated MacBook Pros and a colorful MacBook Neo that’s about to rattle the Chromebook market. As we set our sights on the next big hardware launch, the Apple Watch Series 12 is already on the horizon.
While there haven’t been any concrete leaks yet, there’s plenty we can infer based on Apple’s past launches and typical release patterns. There are also a few lingering rumors that could finally land this year, including a possible nod to a long-removed but not forgotten iPhone feature.
Apple Watch Series 12 launch date
If there’s one thing Apple tends to keep consistent, it’s the timing of its fall hardware event, where it typically unveils its newest flagship iPhones and Apple Watch models.
Apple typically holds this event on the second Tuesday of September (usually the week after Labor Day). By that logic, Sept. 15 seems like the most likely candidate for Apple’s 2026 fall event. Because it lands a bit later in the month than in previous years, there’s also a slim chance Apple moves it up to Sept. 9 (Labor Day week), as it has before.
As in previous years, preorders would likely open on the Friday after the event, with availability following a week or so later (assuming no production delays).
Pricing and availability
Expect pricing for the new watches to stay roughly in line with the current Series 11 lineup, which starts at about $400 (42mm Wi-Fi model). Though price hikes aren’t completely off the table, with lingering tariff increases and the potential for supply chain issues.
How many Apple Watch models will we get?
A Series 12 is all but guaranteed — we’ve had a new Apple Watch model arrive every year since its launch. What’s less certain is whether Apple will refresh the entire lineup again this year. The Apple Watch SE and Ultra models don’t follow the same annual update cycle, and because both the SE 3 and Ultra 3 were refreshed in 2025, it’s less likely that Apple will update both again this year.
If Apple does add another model alongside the Series 12, the Ultra would be the more plausible candidate. Apple isn’t one to hold out on new features for its high-end models when warranted. Or if it follows the pattern set with the Ultra 2, the company might just roll out a new color model for the Ultra 3.
Design upgrades on the Apple Watch Series 12
There are rumblings of a redesign in the works, but given how sparse the chatter has been, my guess is we won’t see a major design overhaul this year. Expect the same silhouette, similar colors and materials. What could change: screen technology. A more energy-efficient display — potentially an improved LTPO panel with better brightness, as seen on the Series 10 — could help claw back some battery life without adding bulk.
Battery life and processor
The Series 11 and Ultra 3 got a significant battery bump over their predecessors: at least 6 hours more by Apple’s numbers and roughly an extra half day (or more) in my real-world testing. And the Ultra 3 also got charging speed worthy of its name, like its newer siblings. But there’s still a lot of room for improvement on both battery life and charging speed.
With no major clues hinting at bigger batteries yet, I’d bet we see more incremental gains (if any) on the Series 12. Improvements could come from better screen technology, software optimizations, and more efficient processors.
In theory, the processor name usually matches the watch number, suggesting an S12 chip this year. But since the Series 11 and Ultra 3 are still running on the previous year’s S10 chip, the next upgrade could technically be an S11, making this year’s naming a bit awkward.
New health features on the horizon
Apple has already dipped its toes into blood pressure monitoring with hypertension notifications on the Apple Watch (Series 10, Series 11 and Ultra 3). The feature alerts owners when it detects signs of abnormally high blood pressure, but it stops short of providing an on-the-spot read. This could be on the table for the fall of 2026.
Other wearable health companies like Omron and Med-Watch have proven that wrist-based blood pressure measurement is possible, though it’s not as reliable as a traditional cuff and may require new (bulkier) hardware to bring to the Apple Watch.
According to Bloomberg’s Mark Gurman, Apple has been testing the feature internally but has encountered accuracy issues. And even if Apple pulls it off for this year, it might measure only baseline trends similar to Samsung’s blood pressure feature on the Galaxy Watch 7 and Ultra (not supported in the US).
Glucose monitoring is another long-running rumor that’s on the table, but according to Gurman, it’s even further from a finished product than blood pressure and realistically wouldn’t appear before 2027.
Biometric authentication: Touch ID or Face ID?
Rumors of a camera on the Apple Watch have been around for a few years — not for selfies, but potentially for Face ID or AI-based image recognition.
Apple Intelligence on the iPhone introduced a visual search tool that uses the camera to identify objects and places in real time, and it might be a matter of time before this feature eventually makes its way to the wrist. Meanwhile, wearable-focused processors like Qualcomm’s Snapdragon chips already support cameras and even livestreaming. Apple is known to use its proprietary chips, so it’s unlikely this would impact Apple’s timeline, but it shows the technology is there, and we may see it down the line on the Apple Watch. Just not this year, according to Bloomberg.
A more feasible near-term option could be Touch ID. Macworld recently spotted lines of internal code suggesting Apple has been experimenting with biometric authentication for the 2026 Apple Watch lineup. According to the report, the code references «AppleMesa,» which is Apple’s internal code name for a watch-based Touch ID. It’s still unclear whether the sensor would be integrated under the display, like we see on Android phones, or built into the side button or the Digital Crown.
Watch OS 27 wishlist
Now that Apple has standardized its operating system names to match the year ahead, you don’t need to be a rocket scientist to figure out that the next big update for the Apple Watch will be WatchOS 27.
With a major redesign already in the books (5 New Apple Watch Features Coming With WatchOS 26), we’re not expecting a dramatic visual change this time around, but there’s plenty on the wishlist, including better battery management tools and more customizable gesture controls. Apple could also expand Workout Buddy from metric-driven encouragement into more concrete training territory. This could bring it closer to what Samsung is trying with its AI-powered Running Coach.
Lastly, I’d welcome a more robust symptom tracker tied into the Vitals app similar to Oura Ring’s Symptom Radar that can flag early signs of illness.
Other Health app updates
The next version of WatchOS 27 could also bring changes to the Health app. According to a report from Mark Gurman at Bloomberg, Apple has been working on a top-secret initiative code-named Project Mulberry, aimed at revamping the Health app with an AI-powered health concierge that could unify your health, fitness, and medical data in one place.
However, the project has recently run into some obstacles. Bloomberg’s latest report suggests Apple has put the effort on hold (at least for this year). That still leaves room for improvement on the Health app front with a potential redesign to the main dashboard that would make spotting trends easier.
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