With the arrival of winter, temperatures in many parts of the country, especially in the north, have begun to decline in the past two weeks. For many new energy vehicle owners, the unfriendly season for driving new energy vehicles is coming.
High voltage batteries, the source of power for new energy vehicles, are also sensitive to temperature and have their own most comfortable temperature range, just like humans. Generally speaking, the normal working state of a battery is between 0 ℃ and 45 ℃. Low temperatures can have a significant impact on battery performance, mainly reflected in the impact on endurance and power performance.
The main factors that restrict the low-temperature performance of lithium-ion batteries are as follows:
1. In low-temperature environments, the viscosity of the electrolyte increases and even partially solidifies, leading to a decrease in the conductivity of lithium-ion batteries.
2. The compatibility between electrolyte, negative electrode, and separator deteriorates in low-temperature environments.
3. The negative electrode of lithium-ion batteries in low-temperature environments experiences severe lithium precipitation, and the precipitated metallic lithium reacts with the electrolyte, resulting in the deposition of its products and an increase in the thickness of the solid electrolyte interface
In low-temperature environments, the diffusion system of lithium-ion batteries within the active material decreases, and the charge transfer impedance significantly increases.
Faced with this issue, new energy manufacturers will also adopt various solutions to ensure that batteries can operate within a reasonable temperature range. For example, the charging preheating strategy has a significant effect on improving the performance of lithium batteries at low temperatures. Electric vehicles can preheat before starting, increase battery temperature, increase battery output power and capacity, and reduce battery aging rate. There are also strategies to optimize battery materials. New energy vehicle manufacturers can improve the performance of batteries in low-temperature environments by optimizing battery materials, such as using materials with good high-temperature resistance to make positive and negative electrodes. In the future, with the popularization of electric vehicles and continuous technological progress, solutions for difficult battery charging in low-temperature environments will continue to be updated and optimized.READ MORE!!
Post time: Dec-12-2023