Regarding the activation of newly purchased lithium-ion batteries, there are many different opinions:
The charging time should exceed 12 hours, and this process should be repeated three times to activate the battery.
The claim that the first three charges should be over 12 hours is clearly a continuation of the misconception about nickel-ion batteries (such as nickel-cadmium and nickel-metal hydride). Therefore, this claim is fundamentally flawed. Lithium-ion batteries and nickel-ion batteries have very different charge-discharge characteristics, and it can be stated unequivocally that all serious, official technical documentation emphasizes that overcharging and over-discharging can cause significant damage to lithium-ion batteries, especially liquid lithium-ion batteries. Therefore, it is best to charge according to standard times and methods, and especially avoid charging for more than 12 hours.
Does the battery need to be activated?
The answer is yes, it needs to be activated!
However, this process is completed by the manufacturer and has nothing to do with the user, nor is the user capable of completing it.
The actual activation process of a lithium-ion battery is as follows: The battery casing is filled with electrolyte – sealed – formation, which involves constant voltage charging followed by discharging. This cycle is repeated several times to ensure the electrodes are fully immersed in the electrolyte and fully activated until the required capacity is achieved. This is the activation process – capacity grading. In other words, lithium-ion batteries are already activated when they reach the user. However, some batteries require the activation process to be in an open state before being sealed. Unless you possess cell production equipment, how can this be accomplished?
But why do some product manuals recommend that users charge and discharge the phone for the first three uses? Isn't this activation? Actually, the truth is that after a battery leaves the factory, is sold, and reaches the user, it undergoes a period of time—a month or several months. During this time, the battery's electrode materials become passivated, resulting in a lower capacity than normal and a shorter lifespan. However, lithium-ion batteries are easily activated. Just 35 normal charge-discharge cycles are enough to activate the battery and restore its normal capacity. Due to the inherent characteristics of lithium-ion batteries, they have virtually no memory effect. Therefore, users do not need special methods or equipment to activate a new lithium-ion battery.
The dangers of overcharging and over-discharging: The rated voltage of lithium-ion batteries, due to changes in materials in recent years, is generally 3.7V, while that of lithium iron phosphate (LiFePO4) batteries is 3.2V. The termination charging voltage when fully charged is generally 4.2V, and 3.65V for LiFePO4. The termination discharge voltage of lithium-ion batteries is 2.75V～3.0V (battery manufacturers provide the operating voltage range or termination discharge voltage; these parameters vary slightly, but are generally 3.0V, and 2.5V for LiFePO4). Continuing to discharge below 2.5V (2.0V for LiFePO4) is called over-discharge. Over-discharge or self-discharge reactions at low voltages will cause the lithium-ion active material to decompose and be destroyed, and cannot be restored. Any form of overcharging of a lithium-ion battery will severely damage its performance and may even lead to an explosion. Overcharging of lithium-ion batteries must be prevented during the charging process.
