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).
Key highlights of the Blade battery structure:
The most intuitive feature is the numerous flat “blades” standing side by side. There is almost no traditional module separator : The interior of the entire battery pack looks like an “array” of blades, without the obvious module frame and compartments found in traditional battery packs.
End plates : At the ends of the length direction of the battery pack, thick fixed end plates can be seen. Simple top connection : The top shows the bus network that connects all the positive and negative terminals of the blade cells.
Bottom cooling system (may be integrated) : The bottom may show integrated cooling piping or cooling plates.
Sturdy shell : The whole structure is wrapped in a very strong shell.
The core advantages brought by the structure.
High space utilization : eliminates module structure and space, and volume utilization is increased by more than 50% . This enables more batteries to be accommodated in the same volume, or makes the battery pack thinner and more compact with the same amount of power (which is beneficial for the interior space layout and wind resistance reduction).
Significant lightweighting : eliminates module structural components and fasteners, reducing weight.
Increased energy density : Higher volume utilization and lightweight directly increase the system energy density of the battery pack.
Enhanced structural strength : The cells are densely arranged in combination with the sturdy end plates and shell to form a honeycomb aluminum plate-like structure, which greatly improves the compressive, bending and torsional strength of the battery pack, enhancing the safety and handling of the whole vehicle (especially in the CTB design).
Excellent safety (especially thermal safety) :
Lithium iron phosphate material itself has good thermal stability, a high decomposition temperature (about 800°C), and is not prone to releasing oxygen. The thin sheet design has a large heat dissipation area, making it less likely for heat to accumulate. There are gaps or heat insulation designs between individual cells to effectively prevent the thermal runaway of a single cell from spreading to adjacent cells (the “firewall” effect). The Blade battery has passed the rigorous needle-puncture test, demonstrating extremely high safety. Longer cycle life : The lithium iron phosphate material itself has a long cycle life (up to 3000 times or more), and the lamination process reduces stress concentration, further extending the life.
Summary:
The core structure of BYD Blade Battery lies in the CTP module-free in-line design of ultra-long thin sheet lithium iron phosphate cells . It achieves the unity of high energy density, high safety and high structural strength by maximizing space utilization, simplifying structural hierarchy and using battery cells as structural components. Imagine a picture of countless slender “blades” standing side by side in a sturdy box, clamped at the ends by heavy end plates, with wires attached to the top and a cooling system at the bottom – that ‘s the essence of the blade battery structure diagram.
