Newly bought mobile phone battery, must be charged more than 12 hours in the first three times?

After we bought a new mobile phone, we often heard the seller say that the battery had to be charged for 12 hours three times. After many users bought it, they basically did it. However, is this really the case?
★★★ The answer is that you don't need to charge for 12 hours.
Early mobile phone NiMH batteries need to be replenished and trickle-charged. It takes about 5 hours to reach the perfect filling state, but it does not need 12 hours. The constant current and constant voltage charging of lithium-ion batteries The feature determines its deep charging time without 12 hours.
For lithium-ion batteries, some people will ask, since the current of the lithium-ion battery in the constant-voltage phase is gradually decreasing, is it true when the current is small to infinity? I have drawn the current in the constant-voltage phase to reduce the time. Curve, it is fitted to the curve multiple times, and it is found that this curve can approach zero current with the function of 1/x. In actual test, because of the self-discharge phenomenon of the lithium ion battery itself, this zero current is never reachable. .
Take a 600mAh battery as an example, set the off current to 0.01C (ie 6mA), its 1C charging time does not exceed 150 minutes, then set the off current to 0.001C (ie 0.6mA), its charging time may be 10 hours - -- This is not precisely available due to the accuracy of the instrument, but the capacity obtained from 0.01C to 0.001C is calculated to be only 1.7mAh, which is more than 7 hours in exchange for more than three thousandths. Capacity does not have any practical significance.
What's more, there are other charging methods, such as the pulse charging method to make the lithium-ion battery reach the 4.2V limit voltage. It does not have the minimum current judgment stage. Generally, after 150 minutes, it is 100% full. Many mobile phones are With pulse charging method.
Some people used to display the fullness of the mobile phone, and then use the charger to charge to confirm the fullness of the phone. This test method is not rigorous.
First of all, the green light is not a basis for detecting the true fullness or not.
★★ Detecting whether the lithium-ion battery is fully charged or not ** The final method is to test the voltage of the lithium-ion battery when it is not charged (and not discharged).
The so-called constant voltage phase current reduction is the real purpose of gradually reducing the additional voltage generated by the charging current in the internal resistance of the battery. When the current is as small as 0.01C, such as 6mA, this current is multiplied by the internal resistance of the battery (generally 200 Within milliohms) is only 1mV, it can be considered that the voltage at this time is the battery voltage without current.
Secondly, the reference voltage of the mobile phone is not necessarily equal to the reference voltage of the charger. The mobile phone thinks that the fully charged battery has reached the charger, but the charger does not think it is full, but continues to charge.