Millions of new cars are welcoming the test of winter life, and the road test in winter is down 24%. In 2018, the country completed the sales of new energy passenger vehicles by 1.08 million units, an increase of 89% year-on-year; the sales in January and February 2019 were 143,000 units, an increase of 134% year-on-year; but the winter road test showed that the average cruising range of the eight models fell 24 %, the lithium cobalt oxide, ternary lithium and lithium iron phosphate contained in the test did not show obvious anti-low temperature advantages, and the market potential of low-temperature thermal management is huge in the future.
High-temperature thermal management has been valued and there are more technical routes for low-temperature thermal management. Due to more than 40 battery spontaneous combustion events in summer, many manufacturers have begun to pay attention to high temperature thermal management, while low temperature thermal management potential remains to be developed. Only a few manufacturers have equipped electric heating systems for batteries; winter battery life is the experience of vehicle manufacturers. The core indicator, the low temperature performance of the battery is the core competitiveness of the battery manufacturer. Every time the low battery life in the winter will promote the penetration of the manufacturer to accelerate the low temperature thermal management, and the market potential is huge in the future.
The inactivity of the electrochemical reaction at low temperatures is the main reason for the decrease in battery power in winter. When the ambient temperature is too low, the viscosity of the electrolyte increases or even partially solidifies, so that the lithium ion deintercalation movement is hindered, the conductivity is lowered, and finally the capacity is reduced. The use of lithium batteries at low temperatures is also prone to irreversible capacity damage to the battery due to the growth of lithium crystal branches and poses a potential hazard. Compared with NCA and lithium iron phosphate, the main battery development direction in China NCM811 has relatively low temperature performance, and the high nickel trend helps to slow down the phenomenon of low electricity in winter.
The development of low-temperature batteries is a fundamental method to solve the decline in winter battery life. High-efficiency thermal management is currently the most feasible winter endurance management solution. At present, the main direction of low-temperature batteries is electrolyte modification and all-weather batteries. The mixed electrolyte can enhance the low-temperature performance of lithium batteries by integrating various electrolytes. The all-weather battery technology has been recognized by BMW as an opportunity to lead the market. The current liquid cooling and heat management technology penetration rate has been greatly improved compared to last year, and the low-temperature heat management can be conveniently realized by reverse heating the cooling liquid. At present, many models have achieved low-temperature heating functions.