Value Appraisals for EVs and Hybrids: Transparency Through Battery Diagnostics

With conventional combustion-engine vehicles, an appraiser focuses on mechanical components such as the engine, transmission, and exhaust system. With an electric or hybrid vehicle, this focus shifts significantly. The high-voltage battery accounts for up to 40 percent of a vehicle's total value. Without a precise diagnosis of this storage system, every value appraisal remains incomplete. A superficial glance at the service book is not enough to determine the actual market value. This is where DIAVAG applies a standardized procedure that goes beyond purely visual inspection. The appraiser comes directly to the vehicle's location, whether that is a home garage or a dealer's business yard.

As part of the Premium appraisal for auf Anfrage, DIAVAG carries out the Premium Battery Test. While inspection organizations such as TÜV or DEKRA often only offer basic diagnostics, this test provides detailed insight into system health. It measures the State of Health (SoH), cell balance, and remaining capacity in kilowatt-hours (kWh). The charging curve and internal resistance are also documented. This data is essential for objectively assessing the battery's remaining service life and performance. A high SoH value is a direct selling point and protects the seller from unjustified price reductions. Buyers, in turn, gain the assurance that there is no hidden cell damage.

Time is a critical factor in vehicle transactions. DIAVAG guarantees an appointment within 24 hours in the regions of Hamburg, Berlin, and Munich. The on-site inspection takes less than 15 minutes. The appraiser uses calibrated hardware, including an OBD2 scanner, a paint thickness gauge for the paint inspection, and a tread depth gauge. The result is a BVSK-compliant PDF appraisal delivered the same day. Every document is signed by a senior inspector. Through certification to ISO/IEC 17020 Type A, DIAVAG operates as an independent inspection body at the highest level. This means there are no economic interests in repairs or vehicle sales.

A value appraisal often serves as the basis for legal disputes or official requirements. Whether in cases of inheritance, divorce, or after an insurance claim, a legally sound document is essential. DIAVAG follows the Judicial Remuneration and Compensation Act (JVEG) to support usability in court. In disagreements with insurers over the replacement value, the detailed appraisal provides a well-founded factual basis. Optionally, the appraisal can be secured with a notarial hash on the Polygon blockchain, further increasing the tamper-proof nature of the documentation. This is especially relevant for high-value assets and commercial fleets.

From February 2027, the EU Battery Passport will become mandatory for new electric vehicles. This regulation requires seamless documentation of the battery's history and condition. DIAVAG has already aligned its processes with these requirements today. By digitally capturing all relevant parameters, a data structure is created that meets future regulatory standards. For commercial fleet operators and car dealerships, DIAVAG also offers an API connection to Dealer Management Systems (DMS). From a volume of 50 appraisals per month, individual terms apply, enabling efficient inventory valuation.