Fast or rapid charging your phone isn’t the real problem. The real enemy is the temperature.
Rapid charging is becoming more common than before. Some smartphones support over 100W charging rates, letting these devices juice up in less than an hour.
But many are concerned about the downsides. Can fast charging damage your phone battery? Is there a way to control the charging speed?
Fast Charging
You’ve probably seen the many marketed charging labels from brands, such as 18W, 25W, 67W, 80W, and so on. The idea of fast charging is to speed up the charging rate of a device so it can be used asap.
In simple terms, the battery and charger work together to increase the wattage or flow of electricity going inside the device. However, most chargers have an output of 5V, as this is the standard. You can see some chargers with 9V or 12V thanks to protocols, such as USB Power Delivery or Qualcomm Quick Charge.
Regardless, your phone battery and the charger that came with it are intelligent enough to handle the electrical flow and prevent issues. This is why you can’t neglect the charger.
Sometimes, apps that can see the phone’s specs fail to detect the fast charging rate. It can happen, especially if the phone battery has a dual-cell configuration. It’s a common design to support higher charging rates by feeding power to two cells at the same time.
Phones with slower charging or standard charging rates often have a single-cell battery design.
Scary Trade-off
Despite innovations in battery design, we’re still stuck in the age where batteries degrade as soon as you use them. Battery degradation after five years of use remains a dream.
When you plug your phone, it starts to heat up even if it’s charging using the standard rate. This is due to the chemical reaction happening inside the battery.
With fast charging, the chemical reaction speeds up too, raising your phone’s temperature quickly. This cycle is what brands are trying to combat using techniques like passive or active cooling systems.
Thus, many users suggest going for slower charging even if you wait for a longer time to extend battery health.
From Fast to Slow Charging
Your phone supports 67W, and when you plug it in at 20%, you see the battery level going back up rapidly. Suddenly, the battery level isn’t going up as fast after a while. Don’t panic or anything.
Remember the heat generated by charging? This is one way to combat it. Fast charging only works at specific battery levels, and that depends on the brand. A phone may turn off fast charging at 50% battery level, while another may do it at 80%.
Another factor that slows down the charging rate is the current heat. There are temperature sensors inside the phone, and when the temperature reaches a threshold, the battery and charger will lower the wattage to prevent overheating. Modern smartphones are smart enough to perform preventive measures.
Managing Charging Speed
Can you control the charging speed? Yes, you can. Some phones have native charging managers that let you disable fast charging.
Unfortunately, many models don’t have that. But there’s a way to manually regulate fast charging: don’t turn off the screen.
Your phone will get to the maximum charging speed if it’s idle and turning off the screen means it can go into idle mode. But what about the screen brightness? What about OLED panels?
Yours truly has experimented on this using the POCO X6 Pro 5G, Xiaomi Mi Max 3, and Infinix NOTE 10 Pro. The first one has an AMOLED panel while the rest have IPS LCD displays.
On both display types, drop the brightness level to the lowest. But for an OLED panel, you need an overlap. Several apps on the Play Store, like this one, simulate the screen off state by placing a black overlay. It works on either panel, though OLEDs gain the best benefit in terms of power saving.
This way, your phone enters a semi-idle mode. It charges faster compared while in use, but slower than in full idle mode. You can also download a temperature monitor to see the estimated temperature.
On my POCO X6 Pro 5G, using a black overlay while charging with its 67W charger maintains max temperatures between 38 and 39℃. If charged with the screen off, the phone can reach up to 42℃. The difference in speed is negligible because the phone reaches 100%, from 20%, at around 40 to 50 minutes in both scenarios.
Takeaway
The troublemaker in fast charging is heat – the bane of smartphones and other gadgets. Although extreme cold temperatures can also damage these gizmos, they’re more prone to hot temperatures because of constant all-day use.
Want to use the peak charging rate? Turn off the screen to let your phone enter idle mode. Better yet, turn the phone off if you’re not expecting calls or messages. But if you’re not in a hurry, you can use an overlay or just keep the screen on at the lowest brightness level.
Want to combat heat? When charging your phone or gaming, use a smartphone cooler. An electric fan works too. But don’t put the device inside a freezer or place ice over it!
Where to point the fan? Check where it feels warmer. It’s usually just below the camera module. Heat can also dissipate on the display itself. You can point the fan on the screen or the back.
An extra tip! Whether the screen is off or on, the phone will charge faster when being cooled. It’ll think it’s safe to go full force because it hasn’t reached the temperature threshold.
