Tesla Unveils 1.2 MW Ultra-Fast Charging System, Adds 480 km Range to Semi in 30 Minutes

On May 12, Tesla unveiled a new 1.2-megawatt (1,200 kW) ultra-fast charging technology specifically designed for its Semi electric heavy-duty truck. The system delivers peak power approximately three times that of Tesla’s existing V4 Superchargers and utilizes dedicated Megacharger stations. The long-range Semi is equipped with an 822 kWh battery pack, which can be charged to about 60% in 30 minutes at 1.2 MW—adding roughly 480 kilometers of range, aligning perfectly with mandatory driver rest periods. The battery pack uses second-generation 4680 large cylindrical cells (dubbed "Cybercells"), derived from the Cybertruck program. Compared to conventional small cylindrical cells, these offer higher individual capacity and require fewer units overall. Combined with tabless/full-tab design, dry-electrode manufacturing, and a structural battery pack architecture, this approach simplifies production and enhances efficiency. The second-gen 4680 cells also feature improved thermal management and current-carrying capabilities, not only meeting the Semi’s high-capacity demands but also laying the groundwork for future passenger vehicles capable of megawatt-level fast charging. Tesla has already planned 66 Megacharger sites across the United States, with 37 expected to be operational by 2026. These will primarily be located along major freight corridors in states like California and Texas to support the large-scale deployment of the Semi.