Battery Degradation and Performance

Comparison between Design and Performance of a BYD Prismatic Cell and Tesla Cylindrical Cell Bridging the gap between lab-scale experiments and larger commercial cells is a key challenge in academic research. Battery cell manufacturers do not typically disclose information on state-of-the-art processes. Disassembling discharged cells inside a glovebox for characterization, electrochemical testing, and documenting internal structure can reveal valuable insights.

OVERVIEW OF GENERAL CELL PROPERTIES AND DIMENSIONS

Teardown analysis of a BYD Blade prismatic cell and Tesla 4680 cylindrical cell allowed for comparison of their electrical, mechanical, material, and process designs. The BYD cell displays half the energy losses per volume as the Tesla cell at the same C-rate. The Tesla cell uses laser welding and BYD cell uses laser and ultrasonic welding for electrode contact. The BYD cell uses a LFP cathode with a graphite anode, whereas the Tesla cell uses a NMC811 cathode with a graphite anode containing PAA and PEO binders. A manufacturing sequence is proposed for both cells.

Battery teardowns provide useful data on internal design, material selection, and performance, but must be done with extreme caution to avoid thermal runaway.

Images of the internal electrode configurations and features for both cells.

Source: [1] Cell Reports Physical Science 6.3 (2025). [2] Journal of The Electrochemical Society 170.12 (2023): 120536. [3] Electrochimica Acta 471 (2023): 143341.

Extracted from the PDF; charts and images may read imperfectly.