Weilai standard battery pack (75kWh) adopts lithium ternary battery and lithium iron phosphate battery mixed arrangement, and adopts the new generation CTP(Cell to Pack) technology. Through Weilai patented technology, the battery pack has achieved excellent low-temperature endurance performance and accurate power estimation ability, providing users with the same performance as ternary lithium battery pack.
Excellent low-temperature durability, low-temperature durability loss reduced by 25%.
Weilai has designed a complete thermal management software and hardware system for the standard battery pack (75kWh). Compared with lithium iron phosphate battery pack, the battery pack's low-temperature endurance loss is reduced by 25%.
Dual system control algorithm:
The original dual-system algorithm performs model control according to the low-temperature characteristics of ternary and lithium-ion batteries. After several rounds of calibration, the low-temperature energy efficiency of the battery system is effectively improved and the low-temperature performance is guaranteed.
Intelligent thermal management of coupled battery heating;
According to the characteristics of increasing internal resistance of the battery at low temperature, the heating model of the battery is developed, and the control target of the battery is dynamically adjusted in combination with the thermal management of the whole vehicle, so as to achieve the balance between minimum energy consumption and driving experience and improve the low-temperature performance.
Physical barrier of total heat dissipation path:?
The battery packs all heat dissipation paths for heat flow analysis, and obtains the source of heat loss in extremely cold weather according to big data analysis. By using low thermal conductivity materials and innovative structural design, heat insulation design is carried out at the key joints of all paths, which can effectively increase the temperature of the battery when it is stopped and avoid energy loss caused by too low battery temperature.
Radiation active thermal compensation:?
In the extremely low temperature environment for a long time, the radiant heating system is actively turned on, which takes into account the energy consumption and temperature uniformity of the battery and ensures that the battery can reach the optimal working temperature quickly. In the extremely cold environment of 12 hours, the minimum temperature of the battery increased by 40% and the temperature uniformity increased by 60%.
The accuracy of power estimation is consistent with that of ternary lithium battery.
The battery power estimation system of ternary lithium iron battery independently developed by Weilai combines the innovation of software algorithm and hardware application, and reduces the power estimation error to less than 3%, reaching the level of ternary lithium battery. Dual system power estimation method: make full use of the advantages of lithium ternary and lithium ferrous phosphate dual systems to realize constant calibration of power estimation and ensure estimation accuracy; High-power DCDC in package: It can realize fast, real-time and balanced power calibration.
Applying new generation CTP technology
In addition, the standard battery pack (75kWh) adopts a new generation of CTP technology, which simplifies the manufacture and assembly by 65,438+00%, improves the volume utilization rate by 5%, and increases the energy density by 65,438+04%, reaching 65,438+042 Wh/kg.
From now on, new car buyers of Weilai can choose ternary lithium iron standard battery pack (75kWh) or ternary lithium long battery pack (100kWh). The model of ternary lithium iron standard battery pack (75kWh) is the same as the original model of ternary lithium 70kWh battery pack, and the price of BaaS is the same.