I was doing some deep dive research into latest EV cell tech and wanted to learn more on BYD Blade Cells. It’s a nice bit of tech.
It’s a long, slim rectangular can, approx 1m in length, made of lithium-iron-phosphate(LFP) chemistry. As its LFP chemistry, energy density is slightly lower, but it does give longer number of charge cycles. A single Blade holds 135Ah and about 432Wh(160Wh/Kg). For perspective, Tesla’s cylindrical 4680 cell(much smaller though) carries just over 23Ah @ 86Wh, but at a higher 241 Wh/kg thanks to its nickel based NMC811 chemistry. LFP gives around 3000 charge cycles, compared to 2000-2500 for NMC811.
BYD folds its electrodes in a Z pattern, laying the layers flat along the length of the can. That geometry shortens current paths, so the cell can rely on simple dual-side bus bars instead of hundreds of welded tabs like Tesla, who rolls its electrodes into a spiral and cuts thousands of tiny virtual tabs along the edges to spread current evenly. 4680 cell puts out more than twice the heat than a Blade cell. BYD cell’s DC resistance is round 60 mΩ, much lower than a typical 4680’s 80–100 mΩ.
A paper from Gorsch et al. puts BYD cell BOM around €62 per kWh, roughly €10 cheaper than the 4680. This delta scales up to significant savings in high-volume production. In a pack, thin water-glycol plates slide between Blade cells, reducing coolant volume by up to 30 percent.
Reg. Pros and Cons. Blade wins on cost, safety, ease of pack cooling and even repair. Single cells can be replaced easily, unlike fully potted 4680 modules, improving serviceability and reducing warranty costs. It loses out on volumetric energy density though, so long-range or high-performance vehicles still lean toward the 4680. Simulations show one blade cell alone can absorb about 18% of a side-impact’s energy before the pack frame even steps in. So it’s quietly acting as part of the car’s crash structure. I think Blade cells are a winner for urban and commercial EVs.
PS: BYD’s battery volume in 2024 was over 150GWh, that’s over a whopping 300 million cells. They are here to stay for sure.
