Any smartphone compatible with the USB Power Delivery (USB-PD) protocol and equipped with at least a 15-watt USB-C power adapter supports fast charging. Now, standard fast charging allows the battery to go from dead to 50 percent in less than 30 minutes.

Manufacturers like Xiaomi have resorted to proprietary technology in search of faster fast charging methods. For example, Xiaomi’s HyperCharge feature boosts the voltage and current values ​​for a faster 210W charge measured in minutes.

Here’s how the 210W charge works and what charging speeds you should expect in real life, including whether such rapid recharging reduces battery health.

Read more: The best new features of Android 14

How does 210W fast charging work?

Xiaomi was the first company to make 210W charging a reality. In November 2022, it featured 210W charging and a 4,000mAh battery that enables it to go from 0% to 100% in 8 minutes.

210 fast charging technology

This technology allows the Note 12 Explorer from Redmi, a subsidiary of Xiaomi, to fully charge its 4,300 mAh battery in nine minutes, or up to 66 percent in just five minutes. In comparison, Xiaomi’s previous 120W HyperCharge technology and Oppo’s 150W SuperVOOC take roughly 15 minutes to charge a 4,500mAh battery.

As if that wasn’t enough, Xiaomi upped the ante by previewing its 300W charging that fully charges the 4,100mAh battery in less than five minutes, setting a new record.

Charging power, expressed in watts, is the product of voltage and current. The higher the voltage or current, the higher the charging power. To make 210W charging practical, reliable and safe, Xiaomi uses a dual GaN power adapter and three special 100W GaNFast chips from Navitas with more than 50 safety features.

210 fast charging technology

The proprietary silicone provides protection against overheating, overcurrent and USB input voltage and more for the charger and phone. It monitors data from multiple sensors in the phone to keep battery thermal performance within safety margins.

The 210W charger uses an improved electrolyte formulation and battery materials such as graphene for greater conductivity than traditional lithium-ion batteries. This increases the performance of the electrodes while reducing their size, allowing the cells sandwiched between the thermal materials to quickly store and discharge energy without wasting much energy on heating.

Standard fast charging gradually reduces the speed from the limit of 80%, which is one of the ways to improve battery life. Xiaomi’s own Mi-FC technology allows more watts to cross the 80% mark. This approach helps shorten the waiting time after 80% to fully charge the battery.

How does 210W charging affect battery life?

Doesn’t 210W charging drain the battery capacity very quickly and significantly reduce its lifespan? The answer to this question is negative. Xiaomi’s HyperCharge maintains up to 80% battery capacity after 1,000 charges, which is well within the margin of any conventional battery.

210 fast charging technology

According to a study conducted by ResearchGate, smartphone customers can expect battery health to drop below 80 percent after 500 to 1,000 full charge cycles.

For example, iPhone batteries are designed to retain up to 80% of their capacity after 500 full charge and discharge cycles. Xiaomi says that the capacity of each battery, regardless of wattage, will decrease by 20% within two years. However, this claim is yet to be proven as these devices are still brand new. If you’re really not in a rush, you should use slow charging mode to maximize your battery life.

Realistic expectations of charging speed

210 fast charging technology

Various factors affect charging speed in the real world. If the power adapter makes a lot of noise or the battery gets hot, the charging speed will decrease. What phone manufacturers don’t tell you is whether such fast charging is bad for battery life.

You may need to turn on the Boost Mode option in the battery section on your Xiaomi to enable 210W charging in the first place.

In addition, people could not reach the rated charging speed in actual use. However, you will experience slower charging compared to Xiaomi’s tests conducted under ideal conditions. For example, Redmi Note 12 Explorer Edition averages 15 minutes from 0% to 100%. Factors affecting charging speed include battery life, room temperature, and even software updates.

Meanwhile, Xiaomi is working on confirming 300W charging. Now, the possible disadvantages of super fast charging smartphones will make you wonder.

However, there are physical and chemical limits to when increasing wattage starts to harm the health of the battery. We are now approaching the point where increasing the charging speed beyond 210W reduces efficiency.

How fast is enough to be fast?

Can you imagine not long ago, it took two hours to fully charge a phone? Fast charging came to the rescue, promising a 50% charge in less than 30 minutes. And with a 210W charger, the battery can be charged up to 66% with a quick five-minute charge.

Now we have reached a point of convenience where we can use the phone for hours after only a few minutes of charging. Soon we will get to the point where when you make yourself a sandwich and before you eat it, you will have 100% charge.