High-voltage battery diagnostics with the mega macs
The high-voltage battery is considered the heart and most expensive component of a battery electric vehicle (BEV). Crucial factors such as performance, range and overall value of the vehicle are directly dependent on the capacity of the lithium-ion drive battery. The power packs, made up of up to 120 battery cells, are part of the e-vehicle underbody and are not easily replaceable. Thus, knowledge of their state of health (SoH) is of significant interest to retailers, workshops, insurers, banks, fleet operators and, last but not least, vehicle owners.
With the ‘Basicʼ battery diagnosis and the certified ‘Proʼ battery diagnosis, Hella Gutmann is pursuing two solutions for the different requirements of the interest groups. The ‘Basicʼ evaluation of the SoH by reading out the vehicle’s internal parameters gives garages the opportunity to quickly make a statement on the condition of the high-voltage storage unit, for example, as part of their service. The parameters defined in the battery management system by the respective vehicle manufacturer, such as cell voltages, cell resistances and SoH, provide information for detecting low-power cells. They also form an excellent basis for good customer advisory services, for example with regard to optimum usage behavior and maintaining the value of a vehicle. HV battery diagnostics ‘Basicʼ can be carried out in a few minutes with the latest mega macs devices from software version 67 as part of the e-mobility functions.
In addition, to enable an assessment of the SoH independent of manufacturer definitions and thereby objective vehicle evaluation, Hella Gutmann is developing the HV battery diagnosis ‘Proʼ in cooperation with Battery Quick Check GmbH, a joint venture of TÜV Rheinland and TWAICE Technologies GmbH. The pool of expertise incorporates the partners’ expertise in vehicle data, energy storage analysis algorithms and certified data processing. Unlike existing solutions on the market, Hella Gutmann and its partners do not rely on time-consuming battery strains while driving. Instead, software-controlled strains are carried out via the mega macs X diagnostic device and wallbox during the charging process. Recorded measured values are evaluated algorithmically. HV battery diagnostics ‘Proʼ can therefore be carried out stationary.
Evaluation by proven analysis algorithms provides objective facts on the actual SoH of the high-voltage battery and also allows a conclusion to be drawn about previous usage behavior. This is an important point, because the occurrence of rapid charges or deep discharges significantly accelerates the aging process of a lithium-ion battery. A certificate from TÜV Rheinland documents the manufacturer-independent condition assessment of the high-voltage battery and forms the watertight basis for expert reports and vehicle evaluations. The market launch of the Proʼ HV battery diagnostics is planned in Germany before the end of 2022, following completion of a field test.