Tesla Cybercab battery pack designed for future LFP cells and module-level repair

A pack built to be serviced, not scrapped

Tesla has explained that the Cybercab's battery pack takes a different path from the structural packs it uses in some Model Y builds. Robert Sumpf, Tesla's director of mechanical design engineering for battery modules and packs, described the design in a Cybercab deep dive with the YouTube channel Munro Live, reporting by Teslarati and InsideEVs has detailed. Rather than potting hundreds of cells into one bonded structural block, the Cybercab uses four separate, individually sealed modules, so a faulty module can be isolated and replaced without discarding the entire pack. ²⁴

Sumpf was blunt about the older approach, giving the Model Y structural battery a grade D because it was hard to build and nearly impossible to repair, Teslarati reported. He estimated a fully structural pack gains about 10% more cell volume, but said the issue is the service cost. By comparison, he graded the Cybercab pack an A minus, with Cybertruck scoring a B minus on the same scale. ²

The economics matter more for a vehicle that rarely sits parked. Cybercab chief engineer Eric Earley said replacing an entire pack before half a million miles is a killer on cost, which is why remanufacturing and serviceability were built into the design from the start, Teslarati reported. Tesla says the Cybercab is designed to run at least 500,000 miles. These are design goals described by engineers rather than proven service outcomes, and Tesla has not published repair pricing or module-swap procedures. ²³

Room reserved for LFP, but no switch announced

The most closely watched detail is what Tesla left empty. Sumpf said space beside and beneath the Cybercab's modules was deliberately left so the pack can move to a lower-energy-density chemistry later. So, we protected this pack to go to an even lower energy dense chemistry as we scale and need to bring LFP into the platform, Sumpf said, as quoted by InsideEVs and Teslarati. ⁴²⁶

The Cybercab currently uses Tesla's own 4680 cells with a nickel-manganese-cobalt chemistry. LFP cells store less energy for their size, so a like-for-like swap would cut range; the reserved space allows Tesla to fit additional LFP cells to offset that loss, InsideEVs and Teslarati reported. In return, LFP offers lower material cost, better thermal stability and longer cycle life, which matters for a vehicle charging frequently throughout long daily duty. No date for an LFP version, no cell supplier and no effect on range have been given, and Tesla has not confirmed the switch will happen at all. ²¹⁵

Lars Moravy, Tesla's vice president of vehicle engineering, offered a second reason for the spare room: Tesla did not need as many batteries as it originally thought, Teslarati reported. Tesla told Sandy Munro in early 2025 that it was targeting a Cybercab pack under 50 kWh with close to 300 miles of range, a reported target rather than a confirmed production specification, and no final capacity or range figures have been confirmed. ²³

Fleet context and Tesla's LFP history

Tesla is not new to LFP. The company has previously sold LFP-equipped Model 3s in the United States, and Shanghai-built, rear-wheel-drive base versions of the Model 3 and Model Y sold in Europe use LFP cells, e-cars.hu reported. The difference with the Cybercab is that the option was designed in from the start rather than retrofitted into an existing construction. LFP has also become the most widely used EV battery chemistry globally over the past year. ¹²

For a fleet-operated robotaxi, battery wear accumulates far faster than on a private car that sits parked most of the day, and downtime while a pack is replaced is lost revenue. Because Tesla plans to keep most Cybercabs in its own transport service, battery repair costs land on Tesla's own books, giving the company a direct incentive to design for cheap service, Teslarati's reporting of the programme suggests. Elon Musk has said the vast majority of Cybercabs will stay Tesla-owned. ²³

Production pace and delivery timing

The battery detail comes alongside production news. Moravy said the Cybercab line at Giga Texas is now building robotaxis faster than Tesla can deploy them. We don't run every day because the line can run so fast. It's currently outpacing our deployments, he said in the Munro Live deep dive, as reported by Teslarati. The unboxed manufacturing process, with front, rear, side and centre modules built and tested in parallel, uses roughly 50% less floor space per vehicle, and the line runs at about 78% automation. ²

Tesla is aiming to deliver the first Cybercabs to outside customers by the end of 2026, Teslarati reported, with the company having said Cybercab service will launch in Dallas in November. Every unit built so far has gone into Tesla's own fleet since the line moved into volume production in April. Texas DMV records cited by Teslarati listed 544 Cybercabs authorised for Tesla's Robotaxi fleet, more than the 507 Model Ys on the same roster for the first time. ²

The Cybercab has no steering wheel or pedals, and in September US regulators opened an investigation into how Tesla certified the car, The Next Web reported. Any LFP change would come against that regulatory backdrop, and no Australian availability for the Cybercab has been announced; the reporting and programme covered here concern the United States robotaxi market. ⁴²