Lithium battery charging knowledge

Charging voltage
Generally, the battery voltage of a mobile phone is written as 3.7V, but the voltage of a general charger is written as 5V, which will not affect the use, because there is a charge management chip inside the phone that is responsible for step-down constant current charging.
No. 5 cylindrical lithium battery, or 14500 battery. Through the technology of a lithium battery voltage regulator, the voltage of the battery is adjusted to a 3.0V voltage suitable for small appliances.
As for the "activation" problem of newly purchased lithium-ion batteries, there are many sayings: the charging time must exceed 12 hours, and it must be repeated three times in order to activate the battery. The statement that "the first three charges require more than 12 hours of charging" is clearly a continuation of the statement from nickel batteries (such as nickel cadmium and nickel hydrogen). So this statement can be said to have been misinterpreted from the beginning. The charging and discharging characteristics of lithium batteries and nickel batteries are very different, and it can be very clear that all serious formal technical data emphasize that overcharge and overcharge can cause significant harm to lithium batteries, especially liquid lithium ion batteries. Therefore, it is best to charge according to standard time and standard methods, especially not to charge for over 12 hours.
The battery also needs to be activated. However, this process is completed by the manufacturer, which has nothing to do with the user, and the user has no ability to complete it. The real activation process of a lithium ion battery is as follows: filling the lithium ion battery shell with electrolyte - sealing - formation, which means constant voltage charging, and then discharging. After several cycles, the electrode is fully soaked in the electrolyte and fully activated until the capacity meets the requirements. This is the activation process - capacitance, which means that the lithium ion battery has already been activated on the user's hand after leaving the factory. In addition, the activation process of some batteries requires that the batteries be in an open state and then sealed after activation.
The instructions for some products state that it is recommended that users fully charge and discharge their phones for the first three times of use. In fact, the fact is that after the battery leaves the factory, it is sold, and then it reaches the user's hands, it will experience a period of time, one month or several months. As a result, the electrode material of the battery will "passivate", at which point the capacity is lower than the normal value, and the service life will also be shortened. However, lithium batteries are easy to activate, as long as they undergo 3-5 normal charging and discharging cycles to activate the battery and restore its normal capacity. Due to the characteristics of lithium batteries, they have almost no memory effect. Therefore, users do not need special methods and equipment during the activation process of new lithium batteries.
Long charge and deep charge
Long charging may cause overcharge. Lithium batteries or chargers will automatically stop charging after the battery is fully charged, and there is no so-called "trickle" charging that lasts for more than 10 hours for nickel chargers. In other words, if your lithium battery is fully charged and placed on the charger, it is also white charged. "None of us can guarantee that the characteristics of the battery's charge and discharge protection circuit will never change and the quality will never be compromised, so your battery will remain on the brink of danger for a long time.". This is another reason why we oppose long-term charging.
On some machines, if the charger is not removed after charging for a certain period of time, the system will not only not stop charging, but also start a discharge charging cycle. Perhaps the manufacturer of this approach has its own purpose, but it is obviously detrimental to the battery life. At the same time, long-term charging takes a long time, often at night. According to the situation of China's power grid, the voltage at night in many places is relatively high and fluctuates greatly. As mentioned earlier, lithium batteries are very delicate, and their ability to withstand fluctuations in charge and discharge is much worse than nickel batteries, which poses additional risks.
In fact, shallow placement and shallow charging are more beneficial for lithium batteries. Only when the product's power module is calibrated for lithium batteries, deep placement and deep charging are necessary. Therefore, products powered by lithium batteries need not be rigidly bound by the process, and everything should be convenient and charged at any time.