Tesla Cybercab: new details on the battery, motor, and production
The YouTube channel Munro Live has been recommended here several times already. Recently, the channel has often covered topics other than electric cars. However, with a video dedicated to the Tesla Cybercab, the American engineering company has once again hit its target. Tesla engineers explain the Tesla Cybercab. And it’s not about autonomous driving technologies, but rather production, the battery, and the engine.
Tesla’s chief engineer, Lars Moravy, Cybertruck development lead Eric Earley, and other experts are surprisingly open about the technology. The video from the Gigafactory in Texas, where the Tesla Cybercab is produced, is almost an hour and a half long and is in English. We’ve compiled the most interesting insights.
Unboxing Process | Battery/BMS | Thermal Management/Engine
Unboxing Process
It begins with the Unboxing process, which is the unique manufacturing method for this model that Tesla has discussed for some time. The basic idea is to work on individual body parts in parallel, thereby improving the workflow. For example, robots can work simultaneously from all four sides on the front module. The number of workstations is expected to drop to just 25 compared to the Model Y.
Munro Live video on the Tesla Cybercab
Part of the Unboxing process is also Gigacasting, already used in other models, which is the casting technique for producing exceptionally large body panels. With the Cybercab, Tesla goes further: the car features a large amount of aluminum for the front and rear underbodies. These parts are manufactured in a single production step. There’s also the central section with the battery and seats, along with doors that in the Cybercab are designed as scissor doors — mainly because it’s “cool,” as mentioned in the video.
For installing the seats, Tesla uses the same method as the Cybertruck: they are screwed directly onto the battery pack. Afterwards, the battery is inserted into the body from below — avoiding the need to struggle to fit it through the doors later on.
In the front compartment filled with components, in addition to a small 48-volt battery and the thermal management system, the main component is the motor — the Cybercab is indeed a front-wheel-drive vehicle — along with the inverters. The inverter is supposed to be repairable without having to disassemble the entire car. Therefore, elements such as the thermal management system and the air conditioner compressor can be easily removed to allow access to the inverter from above.
The two seats are screwed directly onto the battery
Photo by: Munro Live (YouTube)
Another key concept is modularity. Individual modules are tested before being installed in the car. Additionally, Tesla avoids using high-voltage cables for many components in the front compartment; instead, they are connected through the inverter.
Due to the low front hood, the shock absorbers are not mounted vertically but at a slight angle. The Cybercab also features Tesla’s first Brake-by-Wire system, allowing the brakes to be tested separately. This also eliminates the need for hydraulic pipes.
The front compartment with thermal management right in front
Photo by: Munro Live (YouTube)
Another simplification is that Tesla eliminates traditional painting. Since most of the exterior body is made of plastic, color pigments are incorporated directly into the plastic material.
Battery and BMS (after about 25 minutes)
The Cybercab is powered by a 48 kWh battery pack, as is well known. Like the Cybertruck and Semi, it uses 4680 cylindrical cells. The battery configuration is 88s6p, as explained by battery expert Robbie in the video. This means it consists of six parallel groups of 88 cells connected in series. In total, there are no fewer than 528 cells.
The cells are not secured with foam like in the “structural battery” of the Model Y when it was offered with 4680 cells, but are placed in four modules mounted longitudinally. The energy of an impact is absorbed in part by the battery’s steel casing and in part by the modules. Therefore, Tesla experts describe the battery as “semi-structural.” As a result, the energy density decreases by about ten percent, but it is possible to replace individual modules.
The battery is composed of hundreds of cylindrical cells
Photo by: Munro Live (YouTube)
Among the innovations of the Cybercab is the fact that there is no wiring inside the battery – the connection to the battery management system is wireless via radio. Additionally, the battery management system is not located as an “attic” above the battery but behind it, at the same level. This allows it to be replaced from below. Experience shows that it is more likely for the electronics to fail rather than the battery itself. Moreover, Tesla can do without a pyrotechnic fuse for the battery, as the electronics can cut off power just as quickly.
The battery management system is located behind the battery, not above
Photo by: Munro Live (YouTube)
Thermal management and engine (after about 42 minutes)
Regarding efficiency, one of the engineers says: Usually, tires are the most important factor, followed by aerodynamics (although these factors change in importance at high speeds), and third are thermal management and climate control. For the heat pump, Tesla uses a pure ethylene glycol system. There is no traditional refrigeration circuit with a refrigerant like R1234yf or CO₂. Additionally, the air conditioner compressor has been integrated directly into the thermal management system, eliminating heat losses through pipes.
The thermal management of the Cybercab
Photo by: Munro Live (YouTube)
The Cybercab’s 163 kW front motor is mounted vertically. One of its unique features is that the inverter is placed in front of the motor, on the side farthest from the cabin. This helps reduce vibrations. It also facilitates inverter maintenance, and the connection to the thermal management system is short.
The inverter is the square-shaped component on the left; it is located at the front of the motor
Photo by: Munro Live (YouTube)
Since the Cybercab moves primarily at low speeds, the gear ratio of the input gearbox has been shortened: while most Tesla models have a ratio of around 9, it is 11 here. The motor is still oil-cooled, but the cooling channels are no longer in the laminated steel core but in the aluminum of the stator housing. The inverter is water-cooled. The oil pump operates mechanically here, rather than electrically like in other Tesla models. This means the pump is driven by the rotating parts of the motor.
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