The expert organization DEKRA is already on the market with a new battery quick test for major customers in Germany. The patented process has been validated by the RWTH Aachen and in tests with various vehicle manufacturers. As far as the pure test time is concerned, it usually provides a precise value for the remaining capacity (“state of health”) of a traction battery within a quarter of an hour. “Since the battery accounts for a large proportion of the overall value in electric vehicles, the remaining capacity in used vehicles becomes a decisive value factor,” says Ulrike Hetzel, member of the Management Board and Chief Technology Officer at DEKRA.
The new DEKRA battery quick test is already being used as part of an advanced major customer pilot and will be rolled out further in the coming months. The range of services is initially aimed at customers in the used car management sector, such as leasing companies or large car dealerships. Private customers, for whom the issue of battery condition is generally less risky – among other things due to corresponding manufacturer guarantees – will be addressed at a later point in time.
The test is based on the measurement of battery characteristics during a very short test drive. “A brief acceleration of around 100 meters is sufficient, during which the data is read out via the on-board diagnostics interface,” explains Ulrike Hetzel.
Know-how is in the database and algorithm behind it
The actual know-how, however, consists in classifying the measured values. “The process is based on a very elaborately populated database and a highly complex algorithm,” says the DEKRA board member. “The basic data is determined in advance for each individual vehicle type with measurement runs under a wide variety of conditions; This is followed by a corresponding structuring and further complex calculations, partly with the help of artificial intelligence. We refer to the entire process as ‘parameterization’. The values measured in the test case are then evaluated using these type-specific parameters.”
100 vehicle types on the list by the end of the year
The list of types for which DEKRA can offer the quick test currently includes more than 50 vehicle models. These include volume models from various German and European manufacturers (VW, Mercedes-Benz, BMW, Renault) but also, for example, Asian brands (Kia, Hyundai). “We currently cover around a third of the stock of battery-electric and hybrid vehicles in Germany. We are constantly parameterizing other models,” says Ulrike Hetzel. “By the end of the year we want to have created the database for another 50 vehicle types – then we will be at more than half of the German fleet.”
The demand for determining the “state of health” of the traction batteries of electric vehicles will grow in the coming years. With the state subsidy, hundreds of thousands of vehicles with battery or hybrid drives are new to the market. As soon as these vehicles then change hands, the condition of the battery is a highly relevant factor for the evaluation.
“Especially in the area of used vehicle management, such as when leasing returns, a precise and quick determination of the remaining capacity is particularly important so that the overall process remains economical,” explains DEKRA CTO Hetzel. “With other methods, however, the whole thing usually takes at least hours, sometimes days – including complex charging and discharging cycles. The big advantage is that we can make a high-quality statement within a very short time. No one else on the market offers such a quick process.” www.dekra.de
Read this and other articles on the subject of mobility 4.0 electrically-connected-autonomously in the current eMove360° magazine in german language. Free download PDF here.