Contrasting a BYD Blade prismatic cell and Tesla 4680 cylindrical cell with a teardown analysis of design and performance

Highlights•Design, materials, performance, and process flow of BYD Blade and Tesla 4680 cell are compared•Tesla uses laser welding; BYD combines laser and ultrasonic for electrode connections•Tesla 4680 cell generates 2× the heat per volume of BYD Blade at a 1 C specific load•PAA and PEO binders identified in Tesla 4680 anode warrant further investigationSummaryIn order to provide design guidance for the development of next-generation batteries, this article presents a teardown analysis of two commercial lithium-ion batteries: the Tesla 4680 cell and the BYD Blade cell. Insights into these cells' electrical, mechanical, material, and process designs are provided. The BYD Blade cell displays half the energy losses per volume of the Tesla 4680 cell at the same C-rate. The Tesla 4680 cell utilizes laser welding, and the BYD Blade cell utilizes laser and ultrasonic welding as electrode contacting technologies. Lithium iron phosphate (LFP; BYD Blade cell) and NMC811 (Tesla 4680 cell) are confirmed as electrode materials resulting in energy densities of 160 Wh/kg and 355.26 Wh/l and 241.01 Wh/kg and 643.3 Wh/l, respectively, on the cell level. Both cells utilize graphite anodes without silicon dioxide. Polyacrylic acid (PAA) and polyethylene oxide (PEO) are detected as binders on the anode side for the Tesla 4680 cell. A manufacturing sequence is proposed for both cells.Graphical abstract