At one point or another, you’ve probably left your phone charging straight through the night. And perhaps this question has popped into your mind: How long can you leave your phone on a wireless charger? Is it safe for you, and does it impact your phone?
You can leave your phone charging on a wireless charger for as you want. The charger will only charge your phone until it’s full. That said, you should take your phone off the charger at least sometimes, because constant charging will accelerate the decline of the battery’s performance.
If you regularly leave your devices for long periods as they charge, then this guide is for you. We’ll help you understand whether you can leave a wireless charger plugged in all the time and the disadvantages of wireless charging.
Is It OK to Leave your Phone on a Wireless Charger All Day?
Yes. It is safe to leave your phone on a wireless charger for long periods. However, there are some drawbacks.
First things first: High-quality wireless chargers smartly identify the amount of power necessary for the phone. So, even if you leave it overnight, the wireless charger will only power your phone until the battery is full.
Your smartphone battery should be full after a few hours of charging. What happens to your phone after it’s fully charged?
Well, there are chips in your smartphones that play various roles. For starters, there are some known as protection chips that safeguard your phone. Once your device reaches 100%, it automatically stops taking in more charge to prevent overheating, thanks to these chips.
Modern smartphone technology must include these protection chips for safety. So, you don’t have to be anxious about overcharging because your phone is smart enough to stop charging at the appropriate voltage.
That said, the chips will tell the charging to start back up after the charge falls a few percentage points, so it’s this “trickle charging” may reduce the performance of the battery over time.
Now, we have established what happens to your phone when you leave it on charge for long periods, but what happens to the wireless charger? Most models have protection chips. So, once your phone is fully charged, they detect that it has stopped taking in current and stop supplying power.
Can Wireless Chargers Damage Your Phone?
Studies by the University of Warwick have proven that wirelessly charging your phone can reduce its battery’s lifespan.
According to the researchers, wireless charging uses energy transmission through an air gap, thus generating heat. Since the surfaces of the phone and charging pad are in close contact, the heat exposure shortens the phone’s lithium-ion battery life over time.
This is because lithium-ion batteries are sensitive to temperatures exceeding 30 degrees Celsius.
In an example found in the study, a smartphone reached 27.5 degrees celsius during standard charging but spiked to 30.5 degrees celsius with wireless charging, going beyond the maximum temperature for lithium-ion battery cells.
Misalignment (when the charging pad and the phone’s coils are not directly on each other) worsens the situation. That’s because the charger raises the transmitter power to adjust to the problem, leading to more heat transmission — and the possibility of battery damage.
Unfortunately, the coil area is not easily visible, making it difficult to avoid this challenge.
Ultimately, the decision is up to you. You have to decide whether the ease of smartphone charging is worth reducing the batteries’ durability.
Can You Leave a Wireless Charger Plugged in All the Time?
Yes. You can leave a wireless charger plugged in all the time because whenever it’s not charging, it stops transmitting current and no energy is lost.
When a device is on the charging mat or nearby, your wireless charger’s circuit detects it, switching on a charging field. As it waits for your phone to charge fully, this plugged circuit consumes energy, causing some heat emissions.
Then, once the device is all powered up, the charging pad turns off automatically.
It’s also safe to leave your phone on the charging pad or mat overnight or for an extended time because most charging pads trickle-charge your phone battery to keep it fully powered. Trickle-charging occurs when the battery drops below 100% while on the pad, and a little current is delivered to the battery to maintain its fullness.
This means that the wireless charger only powers your phone at the same rate the battery self-discharges power, thus allowing you to safely leave your device on your charging pad all night or for long hours during the day.
The chargers, however, lose a lot of energy while charging. They use the electromagnetic induction process to transfer power from the charging mat to your phone, and this process is possible using two physical coils, an induction coil (found in the wireless charger), and a receiver coil (located in the phone).
This is why you should check that your charging pad aligns precisely with the coils. If you don’t, it will use up more energy and charge slowly.
However, even when properly positioned, wireless charging is less efficient than plugging in your phone.
What Are the Disadvantages of Wireless Charging?
Wireless charging is highly convenient, since you don’t have to deal with tangled cables. However, wireless charging has some drawbacks to consider. Here are some wireless charging pitfalls:
- Relatively costly: Like most new technological devices, wireless chargers are relatively expensive compared to cables. However, you can find some relatively cheap options that should do the trick, like this wireless charger from FDGAO (on Amazon).
- Gadgets can’t be used while charging: Forget about using your phone while it’s wirelessly charging. Once you place it on the mat, you should leave it until it’s full. This isn’t the case when using wired charging.
- It’s slow: Wireless charging takes up to 30-80% longer to fully power up your phone, compared to wired charging. How you position your gadget on your charging mat also determines its charging time, and in most cases, 20% of the power flowing into your device goes to waste.
- It’s scarce: Wires, cords, and cables are easily accessible. For instance, even if you accidentally forget your charger at home, you’ll likely find one at your workplace, school, friend’s house, etc. Wireless chargers, on the other hand, are a different story. If you forget your charging pad, you’re unlikely to find another and may have to use a wired charger.
- Discourages portability: USB cables and chargers fit comfortably into your pocket. Unlike cords, wireless charges are not easily transportable because of the relatively large size of the mat.
- Charging alignment issues: It’s important to confirm that your phone is in the correct position when you place it on a charging mat; otherwise, your device won’t charge. If you also accidentally move your phone from the charger, it will disconnect from the charging pad and you may wake up to an empty battery.
- Not entirely wireless: A wireless charger doesn’t eliminate the use of a cable, especially for portable devices. Peripheral attachments such as a charging pad must connect to a power supply. The only exception is a power bank, which can supply a charge via induction charging. So, technically, you must plug your ‘wireless’ charger into a power outlet.
- Targets high-end phones: Wireless charging primarily favors high-end phones like the latest iPhones and Samsung Galaxy phones. They also require specific accessories like a charging pad or mount, which are far more expensive than cable chargers.
- Various technological standards: Finally, Inductive charging technology uses a variety of technological standards. They include Qi, a product of the Wireless Power Consortium, Open Dots from the Open Dots Alliance, and Rezence from the Alliance for Wireless Power.
Since these standards are different, the wireless chargers are not compatible with all devices. Still, you can find some chargers that are compatible with many of the latest phone models, like the Anker Wireless Charger (on Amazon).