Technical features of BYD blade batteries ：
The BYD blade battery adopts the CTP (Cell To Pack) design concept. The battery cells are directly installed in the battery pack shell as arrays, eliminating the need to assemble the battery cells into modules . This design can maintain the strength of the battery pack, without the cross beam, longitudinal beam and various bolts and other accessories, so as to improve the space utilization inside the battery pack housing, to achieve the total capacity of the battery pack and energy density. The shape of the blade battery is a flat rectangle, which not only improves the heat dissipation effect, but also demonstrates its high safety and strength through needle tests and heavy truck rolling tests.
Production technology
BYD Blade battery adopts lamination process. Compared with traditional winding process, lamination process has better performance in internal resistance, internal temperature consistency and internal stress. The blade battery cell length is 960mm, the thickness is 13.5mm, and the height is 90mm. In the production process, BYD carried out a dust-free design on the workshop, and the key processes reached the hundred-level standard to ensure the cleanliness of the production environment. The coating process supports a maximum width of 130cm, and the rolling process ensures a consistent electrode thickness and a lamination speed of 0.3 seconds per piece, the highest in the industry. In addition, BYD has independently developed pressurized liquid injection technology for the space capsule to ensure full injection of electrolyte.
Energy density and driving range
The energy density of the BYD blade battery is 50% higher than that of the traditional iron lithium battery, making the single-motor version and dual-motor version of the driving range of 605 km and 600 km, respectively. The blade battery design increases space utilization from 40% to 60%, and is expected to increase vehicle battery life by 20% to 50%. Byd plans to increase the energy density of the single unit to 180wh/kg and the system energy density to 160wh/kg in the next two years, which will further enhance the performance and competitiveness of electric vehicles.
Safety and longevity
The BYD blade battery passed the needle test and the heavy truck rolling test, demonstrating its high safety and strength. Its design allows for a large heat dissipation area and a long internal loop, reducing the risk of temperature rise. The lithium iron phosphate anode material has a low risk of thermal runaway, and the possibility of internal pressure increase and temperature increase is small, thus avoiding explosion and combustion. The blade battery is designed to last up to 8 years and more than 1.2 million kilometers, meeting the needs of the full life cycle of the vehicle.
The structure of the blade battery is its innovation and advantage
Core structural concept: CTP (Cell to Pack)
The most innovative feature of the Blade Battery lies in its module-free design , which bypasses the traditional three-level structure of “cell → module → battery pack” and directly arranges and fixes long strip-shaped cells (single cells) in the battery pack , forming a two-level structure of “cell → battery pack”. This is the CTP (Cell to Pack) technology.
Description of key structural components:
1. Cell :Shape : A very long and thin rectangular battery cell (like a “blade” shape). Typical dimensions are 0.6 m to over 1 m in length , 10 cm in width and only 1-2 cm in thickness .
2. Internal structure : uses lithium iron phosphate as the cathode material. The positive electrode sheet, negative electrode sheet and separator are stacked by lamination process (rather than winding) to form the internal structure (imagine a pile of very long rectangular cards stacked together). The lamination process improves the utilization rate of the internal space and the uniformity and stability during charging and discharging.
3. Function : A single cell is both an energy storage unit and a structural component.
Structural Components & Fixation :Arrangement : Many long, strip-shaped blade cells are closely arranged side by side vertically inside the battery pack (imagine many blades inserted side by side in a box). Adjacent cells are usually separated by insulating and conductive material.End plate fixation: The two ends of the array of cells (in the length direction) are clamped together by strong high-strength end plates (imagine a bookstand clamped against a stack of books), providing the main axial binding force.
4. Lateral restraint: The upper cover and lower tray (shell) of the battery pack themselves provide strong lateral support and restraint to hold the cell array in place, making it a solid whole. The high-strength shell of the battery cell itself also contributes to the structural stiffness (” it is both an energy body and a structural component “).
5. Bonding/snap-fit : The cells may be bonded with structural adhesive or snap-fit between the cells and between the cells and the shell to further enhance the overall structural strength.
6. Electrical connection :
Busbar : The positive and negative poles of each blade cell (usually located at both ends in the width direction of the cell) are connected to the corresponding high-voltage busbar (positive busbar and negative busbar) through the flexible circuit board/aluminum bar (busbar).
Battery management system connection : The sampling harness of the BMS (Battery Management System) is connected to each cell or cell group to monitor critical parameters such as voltage and temperature.
7. Thermal management system :
The cooling plate is usually located at the bottom of the battery pack (integrated on the lower tray), or there are cooling channels (air-cooled or liquid-cooled channels) between closely arranged cell groups.
The thin sheet form of the blade battery itself is conducive to heat dissipation (with a large surface area), and at the same time, the thermal stability of the lithium iron phosphate material itself is relatively high.
8. Battery pack casing :
The upper cover and lower tray are made of high-strength aluminium alloy (or steel-aluminium mixture) . It provides protection against sealing, water and dust, and collision and impact. It is a key component of the overall vehicle chassis structure strength (the integrated design of the vehicle body and battery, such as the cornerstone of CTB).
