Participant information for the field study

What this is about

You are taking part in a field study of the Akkubrief method. It examines how reliably the condition of a vehicle battery can be estimated from ordinary charging history: how stable the result is on repetition, how often a result is produced at all, and what else it fails on.

What we do

Through the official Tesla interface we regularly read data from your vehicle: state of charge, remaining energy, odometer, charging events, battery temperature, voltage, current, charging power and timestamps. We have read-only access. We control nothing, and we never wake your vehicle.

What you do

Connect once — then nothing. Drive and charge as usual. We ask you to keep the connection for at least ten weeks and to keep charging your vehicle at least once a week. Without charging there are no data points.

What you get

Your signed battery certificate free of charge (normally €79), a second certificate about four weeks later, free monitoring during the study and for six months afterwards, and your raw data as a file.

Public participant list

So that no one can later quietly drop individual vehicles from the analysis, we publish an identifier for your vehicle when you are included — for example “S-017 · Model 3 LR 2021 · 90–110 thousand km”. Your name, your vehicle identification number and your place of residence do not appear, neither in this list nor in the publication.

What happens to your data

Your vehicle identification number is stored in encrypted form only. For the analysis and the publication we use exclusively pseudonymous data without names, without vehicle identification numbers and without location details. We delete your vehicle's raw data 24 months after the end of the study; the pseudonymous analysis dataset remains published permanently, because it is the basis of the results.

Voluntary participation and withdrawal

Participation is voluntary. You can end it at any time, without giving reasons and without disadvantage. We then delete your personal study data and remove you from future analyses. Aggregated results already published cannot be taken back. A certificate already issued stays yours and stays valid.

What this study is not

The Akkubrief is an estimate with a stated uncertainty, not a laboratory measurement and not an official document. This study examines how robust the method is — it does not prove that it is accurate. No one can guarantee that your individual result is correct.

Who runs the study

The study is run and funded by Akkubrief; the method under test is intended to become a paid product. So we are testing our own method, and that is a conflict of interest. Provider details are in the imprint. That is why we preregistered the study protocol in advance in the Open Science Framework — immutable and time-stamped —, publish the results regardless of whether they favour us, and make the dataset and analysis code public.

Consent declaration

I consent to Akkubrief reading, storing and pseudonymously analysing my vehicle's data as part of the field study, and to publishing the results in pseudonymous, aggregated form. I have read the participant information and I know that I can withdraw my consent at any time without disadvantage.

You confirm this sentence later, in the enrolment step. It is stored verbatim so that it stays provable what exactly you agreed to.

Consent version: 2026-08-18 · 2026-08-18