BYD Seal U DM-i: what independent tests measured on electric range and fuel use

What ADAC measured on electricity

The German motoring club ADAC tested the Seal U DM-i Design AWD, the 238 kW (324 PS) version with an 18.3 kWh lithium iron phosphate battery. The car was a BYD press car first registered in June 2024, priced at 45,990 euros as tested with a six-year or 150,000 km general warranty. It is no niche model: ADAC notes it was among Germany's ten best-selling plug-in hybrids in 2025, with 8,674 sold.^1,2

Starting with a full battery, the car covered 65 km on the electric part of ADAC's Ecotest, a mixed cycle, before the engine started. The WLTP figure for this version is 70 km, or 98 km in the WLTP city cycle. Range therefore held up reasonably well.^1,2

Efficiency did not. ADAC measured 27.3 kWh/100 km including charging losses, against a WLTP figure of 20.0 kWh/100 km. ADAC notes that the most frugal rivals manage about 20 kWh/100 km. A full charge from empty took 17.7 kWh from the socket.¹

Fuel use once the battery is empty

The Seal U DM-i is a mainly series hybrid. Electric motors on both axles drive the car even with an empty battery, and the 1.5-litre turbocharged petrol engine mostly generates electricity. It connects to the front wheels only at higher speeds.¹

It is also a heavy and powerful car. The all-wheel-drive version weighs about 2.1 tonnes, reaches 100 km/h from rest in 5.9 seconds and has a payload of under 400 kg. ADAC rates the performance as very good and the efficiency as weak, which is the trade-off a buyer of this version accepts.¹

In hybrid mode with the battery empty, ADAC measured 7.7 l/100 km. That splits into 5.3 l/100 km in town, 7.3 l/100 km on country roads and 10.2 l/100 km on the motorway. The WLTP battery-empty figure for this version is 6.9 l/100 km, so the measured result is about 12% higher. BYD's European page advertises 6.4 l/100 km without naming a version; ADAC's data lists 6.9 l/100 km for this all-wheel-drive one.^1,2,3

Over ADAC's combined assessment of the first 100 km, the car used 2.7 litres of petrol and 17.8 kWh of electricity. It earned three of five Ecotest stars. Charging is slow by current standards: the CCS socket accepts up to 18 kW, and ADAC found a DC charge still takes more than an hour. BYD quotes 35 minutes from 30% to 80%.¹

How it compares with plug-in hybrids in general

Official plug-in hybrid figures assume a lot of electric driving. European Commission real-world data for cars registered in 2021 found real-world CO2 emissions were on average 3.5 times higher than the laboratory values. For 2022 registrations the gap was 314%. The gap for petrol cars was about 21%.⁴

A Fraunhofer ISI study of nearly one million plug-in hybrids from 2021 to 2023 put real-world use at about 6 l/100 km against about 1.5 l/100 km on WLTP. Compact and mid-market models ran on electricity 35–43% of the time. The Toyota Prius Plug-in was at 42.8%.⁵

Those are fleet averages, and none of them breaks out the Seal U DM-i. They show the main risk for any plug-in hybrid, including this one: the official figure is reached only by drivers who charge almost every day.^4,5

Safety: five stars, carried over from the electric car

Euro NCAP rated the BYD Seal U at five stars on 6 December 2023, testing the electric Design version. It scored 90% for adult occupants, 86% for child occupants, 83% for vulnerable road users and 77% for safety assist. On 11 September 2024 Euro NCAP extended the rating to the plug-in hybrid versions, including the Boost, Design 4×4 and Comfort.^6,7

The result page does not say whether extra crash tests were run on the plug-in hybrid. It records weak spots: poor head protection at the base of the windscreen and the stiff windscreen pillars, no score for car-to-car emergency braking in head-on scenarios, marginal rear-seat whiplash protection, a weak driver-monitoring score, and a child presence detection system that was not rewarded. In ADAC's own scenarios, the emergency braking system recognised motorcyclists, pedestrians and cyclists largely reliably.^6,1

Worked example: one week, two ways

Take a week of five 40 km commutes and one 50 km weekend trip, 250 km in all. Each day fits inside ADAC's 65 km electric range. Charged every night, the car would use about 68 kWh of electricity at ADAC's 27.3 kWh/100 km and almost no petrol, assuming conditions similar to ADAC's mixed cycle.¹

Never charged, the same week at ADAC's 7.7 l/100 km would use about 19 litres of petrol. A 400 km motorway trip shows the other extreme. Even allowing the full 65 km on electricity, which ADAC measured on a mixed cycle rather than a motorway, the remaining 335 km at 10.2 l/100 km needs about 34 litres. The WLTP battery-empty figure would suggest about 23 litres.^1,2

The 60-litre tank gives about 775 km on an empty battery at ADAC's average. Charjin's car file lists the Seal U DM-i at 70–125 km of electric range depending on version, with an 18.3 or 26.6 kWh battery. Buyers with longer daily journeys may want the larger battery, though Charjin found no independent test of it.^1,3

What is still unknown

This review rests on one detailed independent test of one version. There is no measured winter electric range for the DM-i, no independent test of the 26.6 kWh battery, and the Commission's published real-world summary does not break out individual models. A single press car with 17,517 km on the clock says nothing about long-term reliability. Charjin did not search recall databases for this model, so check the exact car's VIN or registration with the national recall service before buying.^1,4