Tesla switches auxiliary electronics to 48V

The Tesla Cybertruck features an all-new 48-volt low-voltage system that replaces the traditional and still popular 12-volt system.

The transition from 12 to 48 volts for onboard auxiliary devices was confirmed by Tesla during its Investor Day in March 2023 and implemented in the final product as promised. The main traction battery system that controls the drives is high voltage with a voltage rating of over 800 volts.

The main advantage of higher voltage for auxiliary applications is that the same power can be supplied at lower current, which directly reduces losses and allows the use of thinner wires to save weight and cost. Large vehicles have already used 24-volt systems, but 48-volt is still a rare solution for cars.

Tesla is not going to stop there, simply switching from 12 volts to 48 volts for its own electric vehicles. Automaker wants to help spread 48-volt architecture across the industry. That's why Tesla has sent specifications for the 48-volt system to other manufacturers, and Ford CEO Jim Farley just confirmed he has received them.

Considering his response «Wonderful for the industry!» we can assume that Ford will also want to implement a 48-volt system in its vehicles, potentially starting with some next-generation all-electric vehicles.

In a follow-up post, Jim Farley said, «It's great to read the paper and see that our next generation team is on a similar path.». Let's work together to help the supply base transition to a 48-volt future as well.». This clearly indicates that the next generation of all-electric Ford vehicles will also have a 48-volt system.

Converting from 12 volts to 48 volts is not as easy as one might think, since it requires rewiring the car and (at least in most cases) all new electrical components (every motor, light, sensor and chip) or at least ensuring that they can operate at higher voltages.

The problem is that this requires investment, there are not many suppliers of spare parts and there are no economies of scale at the beginning. The changes also mean that all service centers must be prepared for the new low-voltage system.

Let's also remember that Tesla still uses a 12-volt low-voltage system in its new electric cars, but has already moved from typical lead-acid auxiliary batteries to 12-volt lithium-ion auxiliary batteries.