The nominal voltage of the existing lithium-ion battery design is generally 3.7V, and the final voltage is 2.75V. It is usually considered from the perspective of safer use of batteries; the second is related to electrical products and electrical environment. Of course, the final voltage can be designed to connect to the world, such as 2.5 volts and 2.4 volts, but not including 2.4 volts.

　　If the temperature during discharging is in the range of -20~60°C, the final voltage of the lithium battery is 2.75V, but the lithium battery can actually be discharged, but it cannot work at 2.5V. Production, continue to lose 2.75V and 2.5V possible part, the following 2.5V will hurt the most, plus the battery is not available.

　　Lithium iron batteries are sometimes also affected by the battery voltage. This lithium battery pack is sometimes used as a core lithium battery pack. The discharge damage voltage of the core lithium battery will not be lower than this 2.75 × n. Taking the most commonly used 6-cell battery pack in notebook computers as an example, a 6-cell lithium battery usually uses a combination of 3 strings and 2 pairs. Therefore, the emission voltage of the lithium battery cannot be 2.75V × 3 = 8.25V. In practice, it is less than 2.5V × 3 = 7.5V.

　　Reduced because lithium-ion batteries are relatively expensive, and both single-lithium batteries and multi-cell batteries have protection boards or protection ICs. When the voltage of the lithium-ion battery reaches the final voltage, the battery will send a certain signal through the battery, and the user should remember the operation method.