This raises an important question: Do these fast chargers damage your phone’s battery, or are they totally safe to use? In this article, we’ll explore the science behind battery function and the technologies that manufacturers are developing to protect your device’s battery.
How does a smartphone battery work?
Smartphone batteries are typically made of lithium-ion or lithium-polymer cells, which operate through chemical reactions. When charging, lithium ions flow from the negative electrode (anode) to the positive electrode (cathode), generating energy that powers the device.
Batteries absorb the most energy when they are almost empty. As they are near their full capacity, they absorb less power. This is why smartphone charging slows down once the battery reaches around 80%. With a fast charger, this process happens much faster, but it’s important to note that fast chargers don’t consistently operate at their peak output. The charger only delivers its maximum capacity for a brief period, while the power input adjusts depending on the battery’s current charge level.
Fast charging explained
Fast charging uses higher power levels to recharge a battery more quickly by increasing the voltage or current supplied. Modern fast-charging systems rely on specialised chargers and batteries that can handle the increased power without causing damage. Technologies such as
Why Do Batteries Degrade Over Time?
Repeated charging and discharging take a toll on batteries, but the primary factor behind battery degradation is heat. Excessive heat can cause the battery’s internal structure to crystallise, reducing its efficiency. This is why the goal of many manufacturers is to minimise heat generation during the charging process. Over the years, companies have developed technologies to reduce heat in the battery and mitigate its negative effects on the overall battery health.
While fast charging is convenient, it can degrade the battery over time if not managed properly. The higher power levels generate more heat, accelerating battery wear and reducing capacity over multiple charging cycles. Modern batteries and chargers are equipped with features, such as temperature sensors and power regulation systems, to minimise damage. Although fast charging can shorten battery lifespan when used frequently, devices often slow the charging speed as they approach full capacity to mitigate these effects. As a result, the battery may not last as long as with slower charging, requiring more frequent recharges over time.
Charging technologies over time
Smartphone brands, especially in India, have been at the forefront of charging technology innovations:
OnePlus launched
Xiaomi introduced
Oppo debuted SuperVOOC in 2018, starting at 50W, and is aiming for 300W charging.
Realme launched Dart Charge in 2020 with 65W and in 2024, showcased 320W SuperSonic charging.
Samsung has used
Consumer perceptions and misconceptions
Many consumers believe fast charging always damages batteries, but modern devices are designed with features to manage heat and voltage, minimising harm. Another common misconception is that using third-party chargers will destroy the battery, but reputable third-party chargers that meet safety standards are safe to use.
Some people worry that fast charging is inherently unsafe, but certified chargers follow strict regulations to prevent damage. It’s also often assumed that fast charging continues at high speeds until the battery reaches 100%, but in fact, most systems slow down near full capacity to protect the battery.
Lastly, people may believe that all chargers offer fast charging, but fast charging only works with devices and chargers that support the same technology, like USB-PD or Quick Charge.
Best practices for charging
To extend
The future of smartphone batteries
Looking ahead, the future of smartphone batteries includes promising advancements in solid-state and graphene technologies, which could offer faster charging, longer battery life, and higher energy density. Additionally, sodium-ion and lithium-sulphur batteries are being investigated as eco-friendly alternatives.
By understanding how batteries work, the impact of fast charging, and best practices for maintaining battery health, consumers can make informed choices that balance convenience and long-term battery performance.
