Phone Charging Heat: Normal or Dangerous?

"Hand warmer" when charging
Have you ever had this experience? After plugging in the charger, the phone gradually heats up, as if it has become a "hand warmer" in winter. Some people worry that this is a precursor to battery explosion, while others are used to it. But is it normal for the phone to heat up when charging, or is it a hidden danger? Today we will find out and share some practical tips to make your phone charging safer and more efficient.

Four major culprits of mobile phone charging heat

1. "Side effects" of energy conversion
Charging is essentially the process of converting electrical energy into chemical energy storage. Whether it is a charger, a data cable or a circuit board inside a mobile phone, heat will be generated due to resistance when current is transmitted. Especially when the charger power is high (such as fast charging), the energy loss is greater and the heat generation naturally increases. According to statistics, the energy efficiency conversion of ordinary charging is about 70%-85%, and the 15%-30% of energy lost is mostly released in the form of heat energy.

2. The "double-edged sword" of fast charging technology
Fast charging technology shortens the charging time by increasing the voltage (such as QC protocol) or the current (such as PD protocol), but this also means greater energy loss. For example, the heat generation of 40W fast charging may be more than 3 times higher than that of 10W ordinary charging. Although the addition of chip regulation, charge pump and other technologies has improved efficiency, intensive electron movement will still generate heat.

3. The "superposition effect" of charging and playing
If high-performance applications such as games and videos are running at the same time while charging, the processor and battery will run at high load at the same time, resulting in heat superposition. At this time, the temperature of the phone may soar to over 45°C, far exceeding the human body's comfortable range.

4. "SOS signal" of battery aging
The life of lithium batteries usually drops to 80% after 500 complete charge and discharge cycles. The internal resistance of an aging battery increases, and more electrical energy is converted into heat during charging. If you find that the phone heats up significantly during charging and the battery life drops sharply, it may be a signal that the battery needs to be replaced.

5 tips to say goodbye to "enthusiasts" and extend battery life

1. Choose original/certified accessories
Third-party low-quality chargers may have unstable voltage and increase heating. Certified products such as MFi (Apple) or Qi (wireless charging) are safer.

2. Avoid charging in extreme environments
High temperature (exposure in the car) or low temperature (below 0℃) will disrupt the chemical reaction of lithium batteries. It is recommended to charge in an environment of 10℃-35℃.

3. "Small meals and frequent meals" charging method
Maintaining the power between 20%-80% and shallow charging and discharging can delay battery aging better than charging to 100% every time. Both iOS14+ and Android systems support the "Optimized Battery Charging" function.

4. Tips for physical heat dissipation

• Remove the phone case when charging to improve heat dissipation efficiency
• Place the phone flat on the surface of heat-conducting materials such as glass and metal
• Avoid stacking power banks and phones
  5. "Let go" at critical moments
  When fast charging is urgently needed, turn on the flight mode or close the background application to reduce the running load. When the phone is not used for a long time, keep it at 50% power.

  Conclusion

  Let technology return to comfort
  The heating of mobile phones is the inevitable result of energy conversion, but through scientific usage habits, we can completely make it "cool down". Next time you encounter heating during charging, you may wish to check the charging environment, adjust the usage method, or give the phone a "half-time break". After all, the harmonious coexistence of people and devices is the ultimate goal of technological services.