Many people notice their phones heating up while charging. Regardless of the phone brand or charger being used, some amount of heating during charging is a common occurrence. In this edition of ‘Everyday Explained’, HT Lifestyle spoke to Chandrashekar Patil, professor and dean, department of electronics and communication engineering, Vidyavardhaka College of Engineering, to understand why phones heat up while charging.
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Why does your phone heat up while charging?
According to him, when a phone heats up while charging, it is usually because some of the electrical energy is converted into heat during the charging process. The battery, charging circuitry, and power adapter all have some degree of energy loss, and that loss appears as heat. “Fast charging can make this more noticeable because the phone is handling higher power levels over a shorter period,” highlighted Chandrashekar.
Chandrashekar highlighted that some warmth during charging is normal, particularly during fast charging or when the battery is at a very low charge level. However, the temperature can rise further if the phone is being used heavily while charging.
Gaming, video calls, navigation, and other processor-intensive activities generate additional heat at the same time that the battery is receiving power. A thick phone case, direct sunlight, poor ventilation, or placing the device on a bed or other insulating surface can also prevent heat from escaping efficiently.
Modern smartphones have thermal sensors and charging management systems that monitor battery temperature. If the temperature becomes excessive, the phone can reduce charging speed or temporarily stop charging to protect the battery and other components. Repeated exposure to high temperatures is more concerning than occasional warmth. Lithium-ion batteries age faster when subjected to excessive heat, which can gradually reduce battery capacity and charging performance.
How to prevent heating?
According to Chandrashekar, to minimise unnecessary heating, it is advisable to use a compatible, good-quality charger and cable, avoid intensive activities while fast charging, and keep the phone in a well-ventilated location. If the phone becomes unusually hot during routine charging, shows a temperature warning, develops battery swelling, or repeatedly stops charging because of heat, it should be inspected by an authorised service professional.
Note to readers: This article is for informational purposes only and not a substitute for professional advice. Always seek the advice of a professional with any questions about any condition.
