State of Development


An overview of all important phases of vehicle development.


Development Partners

We're developing the Sion together with well-known suppliers and engineering service providers.

Development News

Blog Post

Sion on Wheels: Collaboration With Team Rosberg Engineering – TRE GmbH

3rd December 2020 – When selecting a suitable axle concept back in 2018, we got together with an expert from the world of motorsport – Team Rosberg Engineering, or TRE for short.

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Blog Post

Manufacturing Update: Prototypes On the Home Stretch

1st December 2020 – News from Roding! We almost finished the production of our prototypes at Roding. Soon we can finally present them to you!

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Blog Post

News from Production: Prototypes Are Taking Shape

29th October 2020 – Today we will give you a current status of the production of our prototypes at Roding. Already in a few weeks we will present them to you. Be curious!

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Development Steps

Faster Into Production With Only One Variant

We do many things differently. For example, we produce the Sion in only one variant and color. This means less development time and shortens procurement, testing and vehicle build. The majority of our components come into the Sion as so-called "carry-over parts" and therefore only have to be tested in the vehicle environment. We also shorten the test duration by focusing on simulations early in the development phase. We have close and good relationships with our partners. We develop new and efficient processes with them right from the start. This saves us valuable time.

Status Quo

Already early in the concept phase we sent our first vehicles (SVC1) on test drives. With that we got direct feedback from those people who were interested in the concept of the Sion. We quickly found enthusiastic supporters who came together in a big community and whose opinions and feedback were integrated into the further development in many points. At the same time, we built Sono Motors, hired a team of one hundred people and developed organizational structures. Of course, a wide network of partners and suppliers was also set up. With the successful completion of the concept phase, we are now in the final third of the design phase. Through loops of design and simulation, all homologation requirements are already tested on the virtual vehicle.

The Next Milestones

In the final stage of the design phase, it is important, among other things, to reach the next stage of vehicle maturity (SVC2). These vehicles are mainly used to calibrate the powertrain and to tune the chassis. At the end of this phase, the next milestone is reached: the development release for the series prototypes (design release PB). Here, the toolings, mainly "soft toolings", are ordered to reach the next level of maturity (SVC3).

The Testing Process

The completion of the procurement phase, which involves tool manufacturing, part production and testing, logistics and pre-assembly, is followed by the MRD (material required date). With that the assembly of the bodies (BIW) and prototypes begins in the prototype shop. Once the first hardware has been completed, the test phase begins. Here, the functional tests and crash tests are carried out to ensure that the requirements from the specification and homologation are met. In the subsequent design update phase necessary changes are incorporated into the virtual vehicle. At the end there is then the milestone design release MB, with the completion of which we then start the procurement of series toolings.

The Production

Here, the production trial begins, the assembly of the first vehicles at our contract manufacturer on the production line (Body Shop and General Assembly). At the same time, the PPAP process (Production Parts Approval Process) is initiated at our suppliers. Now the final tests for the type approval are carried out with vehicles from production. With the successful type approval and the completion of the PPAP, series production of the Sion (SOP) begins.

The Delivery

Getting the Sion onto the road as soon as possible. In September 2021 the first vehicles will roll off the assembly line in Trollhättan. The actual start of production (SOP), which we have set ourselves as a target, will then be at the beginning of 2022. Good project management of course always includes a realistic risk assessment, especially in a company like ours, because transparency and openness are important to us. Our experienced development team continuously evaluates possible risks. In our overview, potential delays due to possible risks are presented transparently. We continuously evaluate all events and development steps in order to be able to react quickly and to avoid delays. Our clear goal is to deliver the Sion at the beginning of 2022.

CAD Handover

  • Extract actual CAD status
  • Handover to prototype builder

Program Restart

  • Strategy defined
  • Communicated to all stakeholders
  • Engineering service provider (ESP) & Full Service Provider (FSS) on board
  • Initial prototype content defined

Scope Definition

  • Definition of vehicle technical specification and requirements

RFQ & Onboarding

  • Requesting quote updates
  • Restarting the partnership with suppliers and prototype builder


  • Minor CAD adjustments by prototype builder to available tooling method


  • Part ordering, manufacturing and delivery

Body in White

  • Body in white (BIW) manufacturing

General Assembly

  • Assembly of all parts to body in white
  • Initial operation

Prototype Shakedown

  • Continuous testing & feedback to virtual vehicle

Part Ordering

  • Procurement of all required parts

Inhouse Build

  • Bench area is set up in house
  • Benches are built in house
  • All parts are connected

Tactic Definition, RFQ, Onboarding

  • Tactic 2020 is derived from strategy
  • Timing and budget are aligned with all stakeholders
  • RFQ (request for quotation), negotiations and quote updates
  • Onboarding of suppliers

Design Work With Partners

  • Progress on the design of the virtual vehicle 
  • Close collaboration with all relevant ESP and FSS

Loops & Feedback to Design

  • Continuous virtual validation of CAD status via CAE 
  • Updates to CAD design according to actual status and targets