Growing concern as vehicles get heavier

Automakers in China are rolling out larger new energy vehicles with longer driving ranges and more smart functions and comfort features. But bigger battery packs, larger bodies and extra equipment are pushing up vehicle weight, raising concerns over energy use and ownership costs.

Data from the Ministry of Industry and Information Technology show that the average curb weight of new passenger vehicles produced in China reached 1,704 kilograms in 2024, up from 1,312 kg in 2012. The pace has also accelerated, with the weight gain during 2020-24 exceeding that recorded between 2012-20.

Several large NEV models from brands including Nio, XPeng, Li Auto and BYD are now approaching the 3-metric-ton mark in curb weight, underscoring the growing challenge facing the sector.

Han Zhiyu, a professor at the School of Automotive Studies at Tongji University, said the rise in vehicle weight reflects the popularity of larger models, especially SUVs, the pursuit of longer driving ranges and the addition of features such as refrigerators, large screens and premium seats.

The pursuit of longer driving ranges has made battery packs a key source of added weight.

Han said a 100-kilowatt-hour battery pack can weigh 500-600 kg. Higher requirements for crash safety and battery protection have also led automakers to strengthen body structures and battery protection systems, adding to vehicle weight.

Cui Dongshu, secretary-general of the China Passenger Car Association, said rising vehicle weight could push up energy consumption and resource use. He said automakers should look beyond simply adding battery capacity and equipment, as heavier vehicles can increase ownership costs and demand for materials.

An electric SUV weighing around 3 tons can consume more than 20 kWh of electricity per 100 kilometers, while reducing vehicle weight by 100 kg could cut electricity consumption per 100 km by about 7.5 percent, according to industry estimates. Over time, higher electricity consumption can add to ownership costs.

Weight can also affect braking. Analysts said that a 10 percent increase in vehicle weight may lengthen braking distance by about 5 percent, adding pressure on braking systems and tires.

Yan Zhangong, a Nio engineer responsible for vehicle structure, said lightweight design should not mean cutting features or reducing user experience. Instead, automakers need to consider whether each added kilogram is necessary and whether better materials, structures and system integration can deliver the same functions with less weight.

Nio has made weight control part of its vehicle development process. William Li, founder and CEO of Nio, has said the company reviews weight targets for each model to avoid adding weight simply for more features.

Tesla has also used integration to control weight. Its electronic and electrical architecture helps reduce the number of controllers and the amount of wiring. The company has also standardized connectors and applied large-scale integrated die-casting, allowing dozens of parts to be combined into fewer components. The approach reduces complexity and helps control weight.

Han said automakers should avoid equating heavier vehicles with better products, adding that technological progress should be reflected in better materials, structural optimization and system engineering rather than the simple addition of batteries and features.

wangyuchen@chinadaily.com.cn