As the temperature drops, the electrode reaction rate also drops. Assuming that the battery voltage remains unchanged, the amount of charge and discharge current decreases, and the power of the rechargeable battery decreases. From the perspective of various environmental factors, the temperature is more harmful to the charging characteristics of rechargeable batteries. The electrical level is closely related to the electrochemical corrosion of the lithium battery electrolyte page and the working temperature. The lithium battery electrolyte page is considered to be charging a Cardiovascular battery. On the contrary, it is the temperature rise, that is, the power of the lithium polymer lithium battery rises. In addition, the temperature will continue to endanger the transportation rate of lithium battery electrolytes. The temperature rise will accelerate, the transportation temperature will decrease, and the transportation rate will slow down, and it will continue to harm the charging characteristics of lithium batteries. However, a high temperature exceeding 45°C will destroy the balance of chemical reactions inside the rechargeable battery and cause adverse reactions.
Damage of lithium battery at low temperature:
When used in a low-temperature natural environment for a short time, or when the temperature is not low enough, the lithium battery only temporarily harms the battery power, but it is not easy to cause permanent damage. However, long-term application in a low-temperature natural environment, or application in a low-temperature natural environment of -40°C, is likely to cause the "freezing" of the lithium battery and cause permanent damage.
In addition, when a lithium battery is charged at a low temperature, lithium metal will be dissolved on the anodized surface of the rechargeable battery, and the whole process is irreversible. This will cause permanent damage to the rechargeable battery and reduce the safety factor of the rechargeable battery. Therefore, many lithium battery devices have protective equipment, so that the battery cannot be charged at low temperatures.
The influence of temperature on the charging of lithium batteries
In the power supply system of pure electric vehicles, temperature control is one of the most important main parameters, and it is also a key element that harms battery performance. In all battery test system software, the temperature must be marked, because the temperature has a great impact on battery performance. Hazards include the internal resistance, filling characteristics, charging and discharging characteristics, safety factors, and service life of rechargeable batteries.
The average charging and discharging working voltage and volume of lithium batteries decrease with the decrease of temperature, especially at -20℃, the charging and discharging capacity and the average charging and discharging working voltage of rechargeable batteries decrease faster.
According to electrochemical analysis, SEI film resistors and aqueous resistors do not change much in the entire temperature range and are less harmful to the low-temperature characteristics of rechargeable batteries; while the charge transfer resistors vary greatly in the entire temperature range, and are different from each other. The comparison between the aqueous solution resistor and the SEI film resistor has a greater range of change. The reason is that with the decrease in temperature, the positive ion conductivity of the lithium battery electrolyte decreases, and the SEI film resistors and electrochemical corrosion resistors increase, which in turn causes the European mother electric polarization, concentration polarization, and photoelectricity at low temperatures. The increase of catalytic polarization is mainly manifested in the charge-discharge curve of rechargeable batteries as the average working voltage and charge-discharge volume decrease with the decrease of temperature.
The best lithium battery application temperature is 0 to 35°C. The specificity of lithium-ion batteries is reduced under low-temperature standards, the charging and discharging ability of rechargeable batteries is weakened, and the use time is reduced. In a short-term low-temperature natural environment, the destruction of lithium batteries is only temporary, and it is not easy to cause harm to the battery power. After the temperature warms up, the characteristics will be restored.
However, if the rechargeable battery is charged in an ultra-low temperature working environment for a long time, the anodized surface layer of the rechargeable battery will dissolve the metal lithium. This whole process is irreversible and will cause permanent damage to the battery power. Because of the product quality problems of the rechargeable battery itself, and its own product quality problems and embrittlement problems, the mobile phone will be automatically turned off at low temperatures. On the one hand, it is for the reason of protecting the battery, on the other hand, it is also because the manufacture of its own battery is not Qualified and caused by aging.
Summary: Because the service platform of lithium battery working voltage is low during low temperature charging and discharging, the low temperature charging and discharging volume is significantly reduced. However, with the development of battery charging at room temperature, the damage will be fully automatically compensated, which is attributable to reversible damage. However, when the low-temperature battery is charged, the temperature is too low or the rate is too high, which usually causes the irreversible production of lithium dendrites and irreversible volume damage of the lithium battery, which in turn endangers the safety factor of the rechargeable battery.
