The high-voltage battery is the heart of a battery electric vehicle (BEV) and is considered the most expensive component. The performance, range and overall value of the vehicle depend on its state of health (SoH). Thus, battery diagnostics is gaining in importance in workshops and in the used car trade.
Hella Gutmann is pursuing two solutions, with the 'Basic' battery diagnostics and 'Pro' certified battery diagnostics. The 'basic' SoH assessment involves reading out the vehicle's internal parameters and gives workshops the opportunity to quickly make a statement about the condition of the high-voltage accumulators, e.g. as part of the service. The parameters defined in the battery management system by the relevant vehicle manufacturer, such as cell voltages, cell resistances and SoH, provide indications for detecting cells with low power. They also form an excellent basis for good customer advice, for example about the best usage behaviour and how to retain the value of a vehicle. 'Basic' HV battery diagnostics can be carried out in a few minutes with the latest mega macs devices from software version 67 onwards as part of the multiple query parameter function.
To be able to assess the SoH beyond manufacturer definitions and thus an objective vehicle evaluation, Hella Gutmann is developing the 'Pro' HV battery diagnostics in cooperation with Battery Quick Check GmbH, a joint venture of TÜV Rheinland and TWAICE Technologies GmbH. Evaluation via proven analysis algorithms provides objective facts about the actual SoH of the high-voltage battery and also allows conclusions to be drawn about previous usage behaviour, an important point, for example, when expert vehicle assessments are carried out for lessors and insurers, because the frequency of rapid or exhaustive discharges blatantly accelerates the ageing process of a lithium-ion battery. In contrast to existing solutions on the market, Hella Gutmann and its partners do not rely on time-consuming battery loads while driving. Instead, software-controlled loads are applied via the mega macs X diagnostic unit and wallbox during the charging process, for example in the workshop. Recorded measured values are immediately evaluated algorithmically. Battery diagnostics from the 'Pro' HV is expected to be feasible within one hour. A final certificate, with the process certified by TÜV Rheinland, documents the condition assessment of the high-voltage battery, independent of the manufacturer, and thus forms the watertight basis for certificates and monetary vehicle valuations.