Tesla's official Cybertruck owner's manual says "Cybertruck uses a 48V lithium-ion low voltage battery." It powers the windows, doors, touchscreen and other low-voltage systems when the high voltage battery is unavailable, and is also a redundant power source for critical systems such as power steering. Tesla writes that using 48 V instead of the 12 V lead-acid battery found in many conventional vehicles lets the Cybertruck operate more efficiently. But we could not confirm any figure for how much efficiency improves.
Besides the large high voltage battery (the one that drives the car), an electric vehicle has a low voltage battery that runs windows, doors, screens and so on. In this article we check, against the official owner's manual, that the Cybertruck makes this low-voltage battery 48 V.
The conclusion: the Cybertruck's low voltage battery is a 48 V lithium-ion battery
The Cybertruck owner's manual (Electric Vehicle Components) says this.
"Cybertruck uses a 48V lithium-ion low voltage battery."
What does this battery power?
The same manual goes on to say:
- When the high voltage battery is unavailable, it powers low-voltage systems such as the windows, doors and touchscreen.
- It is also a redundant power source for critical systems such as power steering.
So a small battery, separate from the large one that drives the car, also takes on the job of backup power in an emergency.
Why 48 V?
The manual gives its reason.
"By using a 48V low voltage battery instead of the 12V lead-acid battery found in many conventional vehicles, Cybertruck is able to operate more efficiently."
Why would a higher voltage be more efficient? In general, electric power is "voltage × current." To deliver the same power, raising the voltage lowers the current. A smaller current means less heat loss in wiring, and the wiring can be thinner, as is generally explained. But Tesla does not say this itself (a general explanation, not confirmed in the owner's manual).
For comparison, the Model 3 owner's manual (Subsystems) lists its low-voltage battery as "Rating 6.9 amp hour, Voltage 15.5V."
Handling cautions (from the owner's manual)
The manual warns about the 48 V low-voltage system like this.
- Because the 48 V system operates at a higher voltage than a typical low voltage system, there is an increased risk of personal injury, arcing or component damage if handled improperly.
- Treat low-voltage components, including cables and connectors, as always energized.
- 48 V connectors are colored blue, and 48 V wires are marked with blue tape.
What we could not confirm
- An official figure for how many percent efficiency improves with 48 V.
- The battery's capacity (a report gives 4 amp hours, but we could not confirm it against the original owner's manual in this article).
- Whether other models (Model 3, Y, S, X and so on) will change to 48 V.
- How 12 V equipment (such as accessories) can be used.
From how the manual is written, we can read the aim of "making wiring and parts efficient and lighter." But we could not confirm the size of the effect or any spread to other models.
FAQ
What voltage is the Cybertruck's low voltage battery?
The official owner's manual says it is a 48 V lithium-ion battery.
What does the 48 V battery power?
When the high voltage battery is unavailable, it powers the windows, doors, touchscreen and so on. It is also a backup power source for things like power steering.
Why 48 V instead of 12 V?
The manual says using 48 V instead of a 12 V lead-acid battery lets the vehicle operate more efficiently. We could not confirm a figure.
Is 48 V dangerous?
The manual warns that because it is a higher voltage than a typical low voltage system, mishandling raises the risk of injury and arcing. Servicing must follow procedures.
Summary
- The Cybertruck's low voltage battery is a 48 V lithium-ion battery (owner's manual).
- When the high voltage battery is unavailable it powers windows, doors and the screen, and also backs up things like power steering.
- Tesla writes that using 48 V instead of a 12 V lead-acid battery lets it operate more efficiently.
- The efficiency figure, the battery's capacity, and any spread to other models are unconfirmed.
Next: we will look, in order, at the design of a single bolt in a Tesla car (coming soon).
Sources (checked 2026-10-15)
- Tesla Cybertruck Owner's Manual, "Electric Vehicle Components" (no date shown): https://www.tesla.com/ownersmanual/cybertruck/en_us/GUID-2233D4D1-D4E5-4897-9A41-DE8593381CAA.html
- Tesla Model 3 Owner's Manual, "Subsystems" (no date shown): https://www.tesla.com/ownersmanual/model3/en_us/GUID-E414862C-CFA1-4A0B-9548-BE21C32CAA58.html
This article is for learning about science and technology, and is not investment advice. Facts and the author's interpretation are kept separate. Figures are AI-generated illustrations.