The working temperature is below -20 ℃, and low temperature has an impact on the positive and negative electrodes, electrolyte, and adhesive of lithium battery packs. Industry companies and research institutions are exploring and tackling the low-temperature resistance performance of lithium batteries, with a focus on improving the process of existing positive and negative electrode materials, as well as creating conditions for batteries to work at low temperatures by increasing the local environmental temperature of the battery. In recent years, the application range of low-temperature lithium battery packs has become increasingly widespread, widely used in energy storage power systems such as hydropower, firepower, wind power, and solar power stations, as well as in multiple fields such as electric tools, electric bicycles, electric motorcycles, electric vehicles, military equipment, aerospace, etc.
The correct usage method for low-temperature lithium battery packs:
1. Lithium ion battery manufacturers need to overcome multiple technological bottlenecks and develop a series of low-temperature lithium-ion battery products. Ordinary lithium-ion batteries have poor low-temperature performance, while iron phosphate lithium-ion batteries cannot drive electric vehicles at extremely low temperatures.
2. When using low-temperature lithium-ion battery packs, it is important to pay attention to waterproofing. After using them in some devices with lower temperatures, the lithium-ion battery should be promptly removed and placed in a dry and low-temperature place for proper storage to prevent and prevent household fire accidents caused by improper use of lithium-ion batteries.
3. Lithium ion batteries have a lower energy density and possess the safety and storage functions of conventional lithium-ion batteries, as well as high and low energy performance. Low temperature lithium-ion battery packs need to have the advantages of high discharge rate, stable product performance, high specific energy, and good safety.
4. When using lithium-ion battery packs, it should be noted that although the batteries are activated at the factory, they enter a sleep state after being left for a period of time, and the capacity is in a virtual state. But lithium-ion batteries are easy to activate, and after about 3 normal charging and discharging cycles, the battery can be activated and its normal capacity can be restored. Due to the inherent characteristics of lithium-ion batteries, they have almost no memory effect. Therefore, users should not use special methods or devices during the activation process of new lithium-ion batteries in their mobile phones.
5. Regarding the charging of lithium-ion batteries, increasing the constant current value of the constant current and constant voltage charging method within a certain current range (1.5C-0.5C) cannot shorten the time to fully charge the lithium-ion battery.
6. The appropriate temperature control for lithium-ion battery packs should be between 0~40 ℃, and in a clean, dry, and ventilated environment with a relative humidity not exceeding 75%, they should be prevented from coming into contact with corrosive substances and kept away from sources of fire and heat.
7. The normal cycle of charging and discharging for lithium-ion batteries is approximately 500-800 times. At the end of their lifespan, lithium-ion batteries must be recycled and disposed of in accordance with local laws. Lithium ion battery packs have the characteristics of large storage capacity, stable operation, and basic no memory effect. They also have advantages in adapting to environmental temperatures. Taking lithium sulfite chloride batteries as an example, the working temperature can range from -40 ℃ to+55 ℃. Of course, when the temperature drops to minus 40 degrees, the capacity will also change to 50% of room temperature. Low temperature has a significant impact on lithium-ion batteries. It should be stored and used at room temperature as much as possible.
Currently, mobile phone batteries are generally lithium batteries, and the chemical reaction rate of batteries is affected by temperature. Prolonged exposure of mobile phones to low temperature environments can slow down battery chemical reactions, leading to a decrease in battery discharge current and a decrease in battery capacity. This may result in situations such as fast battery usage, black screens, crashes, touch screen malfunctions, and inability to access the internet. When entering a warm indoor environment from a cold outside, temperature changes may also cause water mist to condense inside the phone, resulting in circuit board short circuits or other malfunctions.
The working principle of lithium-ion batteries is that the internal electrolyte undergoes chemical reactions to create a potential difference between the positive and negative electrodes, resulting in current. In low-temperature environments, the electrolyte moves quite slowly, which affects the transfer activity of lithium ions between the positive and negative electrodes, leading to a decrease in battery charging and discharging performance.
Low temperature has an impact on the positive and negative electrodes, electrolyte, and adhesive of lithium iron phosphate batteries. For example, the electronic conductivity of lithium iron phosphate cathode itself is relatively poor, and polarization is prone to occur in low temperature environments, thereby reducing battery capacity; Affected by low temperature, the speed of graphite lithium insertion decreases, making it easy for metallic lithium to precipitate on the negative electrode surface,
If the battery is put into use due to insufficient idle time after charging, the metallic lithium cannot be fully embedded in the graphite again, and some metallic lithium continues to exist on the surface of the negative electrode, which is highly likely to form lithium dendrites and affect battery safety;
At low temperatures, the viscosity of the electrolyte will increase, and the migration impedance of lithium ions will also increase accordingly;
In addition, in the production process of lithium iron phosphate, the adhesive is also a crucial factor, and low temperature can have a significant impact on the performance of the adhesive. In low-temperature environments, there are certain risks associated with charging lithium-ion batteries. As the temperature decreases, the dynamic characteristics of the graphite negative electrode deteriorate. During the charging process, the electrochemical polarization of the negative electrode is significantly intensified, and the precipitated metallic lithium is prone to form lithium dendrites, which penetrate the separator and cause a short circuit between the positive and negative electrodes. The above are the application areas and correct usage methods of low-temperature lithium-ion battery packs. With the further development of technology, lithium-ion batteries will have further breakthroughs in low-temperature environments.