What is BYD DM-i and how much fuel does it use if you don't charge it?

What DM-i means and where it comes from

DM means "Dual Mode", meaning the car can run in two modes: electric and gasoline. The letter "i" comes from "intelligent". BYD uses this name for its plug-in hybrids designed for low fuel consumption.

The story begins in December 2008 with the BYD F3DM. It was the world's first mass-produced plug-in hybrid. It had a 1.0-liter engine, two electric motors and a 16 kWh LFP battery, with about 60 km of electric range. Only 48 units were sold in the first year.

Next came the Qin sedan, launched in December 2013 with the second-generation DM: a 1.5-liter turbo engine and a focus on performance. By 2018 another generation, the third, had arrived with gradual improvements. The DM-i system itself was unveiled on November 13, 2020, together with the DM-p performance version. The first production model, the Qin Plus DM-i, went on sale in March 2021.

On May 28, 2024, BYD launched the fifth generation, called DM 5.0, on the Qin L DM-i and Seal 06 DM-i. In 2025, BYD announced an update to this generation with even lower claimed fuel consumption. All the consumption figures below are on the Chinese NEDC cycle, with the battery nearly depleted. NEDC is an old, optimistic test, so the figures can't be compared directly with European WLTP ones.

How DM-i works

A DM-i has three main parts. The first is a 1.5-liter Atkinson-cycle gasoline engine built specifically for the hybrid. BYD calls it Xiaoyun and kept the name for the 2024 generation too. Claimed thermal efficiency rose from 43% in 2020 to 46.06% in 2024. The second is the EHS (Electric Hybrid System) unit, which combines a generator, an electric traction motor and a clutch. The third is the Blade battery, an LFP (lithium iron phosphate) type.

The basic idea: the wheels are driven almost always by the electric motor. The gasoline engine most often acts as a generator and produces electricity. There is no conventional gearbox. ADAC notes a single-speed transmission on the Seal U DM-i, so no gear changes and no jerks.

The car picks the mode on its own, based on speed, load and how much charge is left in the battery.

• Electric (EV): runs on the battery only. This is the usual mode in the city as long as the battery is charged.
• Series: the battery is depleted, the gasoline engine starts and spins the generator. The electricity goes to the electric motor, which drives the wheels. The gasoline engine doesn't touch the wheels.
• Parallel or direct drive: at higher speeds or under hard acceleration the clutch closes. The gasoline engine drives the front wheels directly, and the electric motor helps when needed.
• Watch out when overtaking: ADAC observed on the Seal U DM-i that if you suddenly demand full power with a depleted battery, it arrives only after 2–3 seconds, while the gasoline engine revs up.

DM-i, DM-p, DMO: what's the difference

They are all variants of the same "Dual Mode" family. The purpose differs. DM-i is built for low fuel consumption and usually has front-wheel drive. DM-p ("performance") focuses on power and typically has two electric motors and all-wheel drive. For example, the Tang L DM-p has 400 kW and accelerates from 0 to 100 km/h in 4.3 seconds.

Other names appear at BYD's sub-brands. Fangchengbao (Leopard) uses DMO, meaning "Dual Mode Off-road", for off-road SUVs like the Leopard 5. In Europe, BYD sells these cars under the marketing label "Super Hybrid" or "Super DM". On some new models, such as the Sealion 07 DM, the model name says just "DM", while the actual versions remain DM-i or DM-p.

How it differs from a European plug-in hybrid and from an EREV

In the classic European plug-in hybrid, the gasoline engine does the main work, through a multi-speed gearbox. The electric motor is a helper, integrated into the transmission. Example: the Volkswagen Golf eHybrid sends power through a 6-speed DSG automatic.

With DM-i it's the other way around. The electric motor does the main work, and the gasoline engine is mostly a generator. That's why, in the city, a DM-i feels like an electric car even with a depleted battery.

Compared with an EREV (Li Auto, Voyah Free, Leapmotor C16), the main difference is the clutch. In an EREV, the gasoline engine is never connected to the wheels. In a DM-i, it can drive the wheels directly at high speed, where that is more efficient than turning gasoline into electricity and electricity into motion. In addition, DM-i cars usually have smaller batteries than EREVs, although new models are getting closer: the 2026 Sealion 06 DM-i has 38 kWh and up to 310 km of CLTC electric range.

How much fuel it really uses with a depleted battery

BYD's figures of 2.9 or 2.6 liters per 100 km are on the NEDC cycle. It's an old, short and slow test that gives values far below real ones. For a buyer in Moldova, what matters is consumption with a depleted battery on real roads.

In 2026 ADAC tested an all-wheel-drive Seal U DM-i (the European version of the Song Plus DM-i, with a 1.5 turbo engine, 2.1 tonnes). With a depleted battery it averaged 7.7 l/100 km: 5.3 l in the city, 7.3 l on rural roads and 10.2 l on the highway. Auto Bild measured 6.1 l/100 km with a depleted battery on the Seal 6 DM-i Touring, the European wagon version of the Seal 06 DM-i, with a 1.5 l naturally aspirated engine and the DM 5.0 generation.

The pattern is clear: in the city and at low speeds, where the electric motor does most of the work, DM-i is economical. On the highway, at 120–130 km/h, consumption rises a lot. Our estimate for Moldova: without charging, count on 6–8 liters per 100 km for a compact DM-i SUV, and more if you drive a lot on fast roads.

What maintenance it needs

A DM-i has a gasoline engine, so it needs servicing like a regular car. However, the engine runs fewer hours than in a gasoline-only car, especially if you charge often.

The official service schedule from BYD's importer in Cyprus for the Seal U DM-i (European market) includes the following. Cars brought from China may have a different schedule, written in the Chinese manual, so check it for your model:

• Engine oil, oil filter and air filter: every 12 months or 15,000 km.
• Fuel filter, cabin filter and brake fluid: at 24 months or 30,000 km.
• Spark plugs: at 45,000 km.
• Oil and filter of the EHS hybrid unit: at 48 months or 60,000 km.
• High-voltage battery and its wiring: inspection at 24 months or 30,000 km.

Examples from our catalog

• BYD Sealion 06The 2026 DM-i version uses DM 5.0, a 38 kWh Blade battery and up to 310 km of electric range (CLTC). BYD claims 3.3 l/100 km with a depleted battery (NEDC).
• BYD Seal 06One of the first two models with DM 5.0 (May 2024). The European wagon version, the Seal 6 DM-i Touring, used 6.1 l/100 km with a depleted battery in the Auto Bild test. The Seal 06 also exists as a pure electric.
• BYD Sealion 05Compact SUV with DM 5.0, a 74 kW engine and 12.9 or 18.3 kWh Blade batteries (75 or 115 km CLTC electric). Claimed: 3.79 l/100 km with a depleted battery (NEDC).
• BYD Song LSUV with DM 5.0, launched in July 2024. An example of DM-i on a larger family car.
• BYD Tang LAvailable in both variants, DM-i and DM-p, with a 1.5 turbo engine and a 35.6 kWh Blade battery. Good for seeing the difference between economy and performance.

BYD with DM-i, in stock

The BYD plug-in hybrids we have in stock right now, all with the DM-i system described above, with the final price in Moldova: shipping, customs and registration included.

BYD Seal 052025 · new · Plug-in hybrid€14,490In stockBYD Sealion 052025 · new · Plug-in hybrid€18,990In stockBYD Song Pro2025 · 2,800 km · Plug-in hybrid€20,190In stockBYD Song L2025 · 13,000 km · Plug-in hybrid€23,490In stockBYD Sealion 062025 · 20,000 km · Plug-in hybrid€23,990In stockBYD Tang2025 · 1,000 km · Plug-in hybrid€26,990In stock

All cars in stock

Stock changes daily. As of October 5, 2026.

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