The charging speed of the Mini Power Bank is greatly affected by the ambient temperature.
Judging from the working principle of batteries, whether they are lithium-ion batteries or lithium polymer batteries, these are the types of batteries commonly used in Mini Power Banks. The rate of chemical reactions inside them is closely related to temperature. In low temperature environments, such as below 0°C, the ionic conductivity of the electrolyte inside the battery will be significantly reduced. This is just like a vehicle slowing down when the road is icy. The movement of ions in the electrolyte becomes difficult, which reduces the battery's charge acceptance ability. At this time, the chemical reaction inside the battery cannot fully proceed during the charging process, resulting in a significantly slower charging speed. Moreover, forced fast charging at low temperatures may cause irreversible damage to the battery, such as lithium metal precipitation, which further affects the performance and life of the battery.
On the contrary, in a high-temperature environment, when the temperature exceeds 45°C, although the conductivity of ions will be enhanced, excessive temperature will trigger side reactions inside the battery. For example, the electrolyte may decompose and the stability of the electrode material may be affected. In order to avoid safety hazards caused by battery overheating, such as bulging and explosion, the charging management system inside the Mini Power Bank usually reduces the charging power. Just like when a car slows down its speed in high temperatures to prevent the engine from overheating, the charging speed will also slow down.
In addition, the Mini Power Bank's shell material and heat dissipation design will also have an impact on the phenomenon that ambient temperature affects the charging speed. If the heat dissipation performance of the casing is poor, the heat generated by the battery will be difficult to dissipate in a high temperature environment, and it will be easier to trigger the power reduction operation of the charging management system. In low-temperature environments, poor thermal insulation of the casing may make it more difficult to raise the battery temperature to a suitable charging range, thereby prolonging the charging time.
Therefore, in order to ensure the charging speed and safety of Mini Power Bank, users should try to avoid charging in extreme temperature environments when using it. In the cold winter, you can place the mobile power supply in a warm place to preheat before charging; in the hot summer, avoid exposing the mobile power supply to the sun for charging, and ensure that the charging environment is well ventilated.
