A recently published article in Cell Reports Physical Science presents a detailed teardown of two popular lithium-ion battery cells: Tesla’s 4680 cylindrical cell and BYD’s Blade prismatic cell. The study examines the cells’ design, materials, and performance, providing data that may help guide future battery development.
The analysis points out that the Tesla 4680 cell uses NMC811 chemistry, while the BYD Blade cell is based on Lithium Iron Phosphate (LFP). As a result, the Tesla cell achieves an energy density of roughly 241.01 Wh/kg and 643.3 Wh/l, compared to the BYD Blade cell’s 160 Wh/kg and 355 Wh/l. Although both cells incorporate graphite anodes, Tesla’s design also uses binders such as polyacrylic acid (PAA) and polyethylene oxide (PEO), which could influence its performance characteristics.
Here"s how the two units compare in terms of general cell properties and dimensions:
| Tesla 4680 cell | BYD Blade cell | |
|---|---|---|
| General | ||
| Nominal capacity, Ah | 23.125 | 135 |
| Nominal energy, Wh | 85.56 | 432 |
| Nominal voltage, V | 3.7 | 3.2 |
| Voltage window, V | 2.5–4.3 | 2.6–3.65 |
| Weight | 355 g | 2.7 ± 0.3 kg |
| Volume, mL | 133 | 1,216 |
| Energy density (gravimetric), Wh/kg | 241.01 | 160 |
| Energy density (volumetric), Wh/l | 643.3 | 355.263 |
| The areal capacity of the cathode (calculated), mAh/cm2 | 4.99 | 2.393 |
| Dimensions | ||
| Diameter/length, mm | 46 | 965 |
| Height, mm | 80 | 90 |
| Thickness, mm | – | 14 mm |
| Can wall thickness (sides), mm | 0.4 | 0.3 |
| Separator, μm | 10 | 12 |
| Anode coating thickness, μm | 125 | 65 |
| Copper substrate foil thickness, μm | 10 | 10 |
| Cathode coating thickness, μm | 75 | 70 |
| Aluminum substrate foil thickness, μm | 20 | 20 |
| No. of separator layers | 2 | 78 |
| No. of cathode sheets (coating on both sides) | 1 | 38 |
| No. of anode sheets (coating on both sides) | 1 | 39 |
In terms of design, the Tesla cell employs a cylindrical format with a tabless electrode configuration, a feature reportedly achieved by laser welding. This configuration is intended to maximize energy density. However, the analysis notes that this advantage comes with a drawback: the Tesla cell produces about 23 times more heat per volume at a 1 C specific load than its BYD counterpart, creating additional challenges for thermal management during high-load or fast-charging scenarios.
The BYD Blade battery adopts a prismatic design and benefits from a dual welding approach that combines laser and ultrasonic welding techniques. This method ensures strong electrode connections and contributes to reduced energy losses per volume at similar operating rates. The study finds that the Blade cell’s simpler thermal behavior may lead to improved efficiency and potentially lower production or maintenance costs, despite its lower overall energy density.
The teardown also examines mechanical and manufacturing differences between the two cells. While Tesla has focused on achieving a higher energy density, it does so at the cost of increased heat generation. This extra heat can demand more sophisticated engineering solutions to manage temperature during heavy use. In contrast, BYD’s approach emphasizes efficiency by minimizing energy losses and attaining a better thermal profile. This design trade-off could influence how each battery cell is used in different applications.
Source: Cell Press
This article was generated with some help from AI and reviewed by an editor.