State of Health (SOH) certificate for electric cars: what is in it and what it costs
A measurement is fleeting, a certificate remains. This is what is in the document, how it is created, and why the market is now demanding it.
What is a state of health certificate?
An SOH certificate records the state of the battery pack at the time of measurement, in a document linked to the chassis number of that specific vehicle. It is not a seller's estimate, nor is it a printout from a random scanner.
The core is a single number: the battery's state of health, or the remaining capacity compared to when it was brand new. Surrounding this are the measured values that support that number, so that someone else can verify where it comes from.
The latter is what makes the difference compared to a single measurement. Anyone who looks at the document later can see which car is involved, when it was measured, and according to which standard.
What is in the SOH report
At the top of the electric car SOH report, it states what it is about: make, model, chassis number, and the time of the measurement. That header may seem like a formality, but without that information, a report does not belong to any car and is worthless as evidence.
Below is the assessment. Next to the percentage, you will see a representation of the individual cells, which shows at a glance whether the package is worn evenly or if there are any outliers.
The final part is about usage: how many charge cycles have been completed and what proportion of those took place on a fast charger. Two cars with the same percentage can differ significantly on this point, and that says something about the years to come.
SOH test electric car: how the certificate is created
The measurement itself takes a maximum of three minutes and is done via the diagnostic port. Nothing is disassembled and the car does not need to go anywhere. Our equipment retrieves what the Battery Management System has recorded and compares it with our own database.
An EV SOH test is identical for a plug-in hybrid, only the battery pack is smaller. In both cases, the same document is produced, with the same supporting evidence.
SOH certificate costs
Individuals pay € 80 including VAT for a certificate. That is a fixed amount, regardless of brand, year of manufacture or package size, and there are no hidden fees afterwards.
Car companies that want to do it themselves purchase a one-off toolkit and then pay per issued certificate: € 29.95, excluding VAT. Anyone who certifies ten cars per month knows exactly where they stand.
How much a certificate costs
Private: € 80 including VAT per test, with us or at an affiliated garage.
Business: € 29.95 excluding VAT per test.
Measure yourself with the TBE Toolkit: from € 59 excluding VAT.
SOH certificate remarketing: why the trade is asking for it
Remarketing is all about estimating residual value, and in an electric car, that value is largely contained in a single component. As long as nobody knows the condition of that component, the entire chain calculates with a margin for the unknown.
A certificate removes that margin. The buyer knows what they are purchasing, the auction house knows what it is offering, and the end customer receives substantiation instead of a promise. This speeds up the process and prevents discussions afterwards.
For leasing companies, there is another factor at play: when taking back a car, the condition of the battery pack is often the only point of disagreement. With a measurement at the time of intake, that discussion is resolved instantly.
How do you check if a certificate is authentic?
First, check if the chassis number on the document matches that of the car in front of you. It sounds obvious, but a report belonging to another vehicle says nothing about this car.
Then pay attention to the date and the party that issued it. Our reports are CARA Approved, the European standard for battery diagnostics, and carry a secure reference back to the measurement in our system.
Frequently asked questions about the SOH certificate
What is the difference between a report and a certificate?
The report contains the measured values, the certificate is the official record thereof, linked to the chassis number.
How do I know if a certificate is authentic?
Verify the chassis number, the date, and the issuing party. Our certificates are CARA Approved and traceable to the original measurement.
Does a certificate increase the residual value?
It removes the buyer's greatest uncertainty. You will notice this in the speed of the sale and in the leverage you maintain during negotiations.
What exactly is stated in the TBE certificate?
Vehicle data, the state of health in percent, the remaining capacity, the cell overview, the charging history and a final assessment.
Want to know more? View all frequently asked questions in the knowledge base.
Apply for your SOH certificate
Private individuals make an appointment at our location or at a partner nearby. Car companies issue the certificates themselves using the TBE Toolkit.