Is there a problem with Great Wall reporting BYD's atmospheric fuel tank?

[NetEase Technology reported on May 27] Recently, the car circle is not peaceful, and the events of BYD and Great Wall Motor have been hot twice. Both sides have issued separate statements, sparking a thousand waves among the industry and netizens

[NetEase Technology reported on May 27] Recently, the car circle is not peaceful, and the events of BYD and Great Wall Motor have been hot twice. Both sides have issued separate statements, sparking a thousand waves among the industry and netizens.

So far, what are the main viewpoints of both parties? Where are the points of controversy? Is there a problem with the atmospheric fuel tank? This article aims to clarify the context for readers.

Both parties declare that what is the focus of the debate?

At 10:40 a.m. on May 25, Great Wall Motor issued a statement:

"On April 11, Great Wall Motor submitted the report materials to the Ministry of Ecology and Environment, the State Administration of Market Supervision and Administration, and the Ministry of Industry and Information Technology to report that BYD Qin PLUSDM-i and Song PLUSDM-i use atmospheric fuel tanks, which is suspected of failing to meet the standard of evaporative pollutant emissions of the whole vehicle.

According to the Measures for Environmental Administrative Punishments, the competent environmental protection department shall conduct a preliminary examination of suspected violations of environmental protection laws, regulations, and rules. After examination, those who meet the following four conditions shall be filed:

"At present, Great Wall Motor is paying close attention to the case filing and processing progress."

Subsequently, within less than 2 hours, BYD Motors issued a statement on Weibo in response:

"We firmly oppose any form of unfair competition and reserve the right to legal proceedings!"

Our products and related testing comply with national standards and have been certified by authoritative national institutions

We welcome relevant departments to come at any time for investigation, evidence collection, and testing.

As the first company in the world to launch plug-in hybrid vehicles, BYD has more than 20 years of accumulation and iteration in plug-in hybrid technology, which is not as simple as some peers think

The development of the new energy industry has been quite difficult so far! The growth of Chinese brands has also been quite difficult! I hope everyone can do more things that are beneficial to the industry and Chinese brands

After BYD responded to the statement, the incident reached a climax, causing a huge uproar both inside and outside the industry. The opinions of netizens are also divergent.

However, it is a coincidence that at 3pm that day, it was the launch ceremony of the BYD Song ProDM-i Champions Edition.

Is there a problem with the atmospheric fuel tank?

The key point in the Great Wall statement is the emission of evaporative pollutants.

For ordinary fuel vehicles, this problem is basically not present. The evaporated gasoline will be adsorbed by the carbon canister, and after the engine starts, a negative pressure will be formed. The gasoline vapor adsorbed by the carbon canister will be immediately sucked into the engine and burned.

However, for hybrid vehicles, they are often in EV mode with little or no use of the engine, or the engine has a short running time, which reduces the chance of negative pressure formation. Once the carbon canister is full, gasoline evaporates and is discharged into the atmosphere, becoming volatile organic compounds and causing pollution.

This may be the assertion in the Great Wall statement that using atmospheric fuel tanks will definitely cause pollution.

As the first company in the world to launch plug-in hybrid vehicles, BYD has more than 20 years of accumulation and iteration in plug-in hybrid technology, which is not as simple as some peers think

A netizen has uncovered a patent filed by BYD in 2020, titled "Control Methods, Control Devices, and Hybrid Vehicles for Hybrid Electric Vehicles".

The article mentions that providing a control method, control device, and hybrid vehicle for hybrid vehicles belongs to the field of vehicles. The control method for hybrid vehicles includes: determining the carbon canister adsorption amount based on a pre established carbon canister adsorption model when the vehicle is in electric mode; And when the adsorption capacity of the carbon canister exceeds a preset value, switch the electric mode to hybrid mode for carbon canister desorption. Through the technical solution provided by the present invention, it is possible to estimate the adsorption capacity of the carbon canister without increasing hardware costs such as components, and automatically switch the vehicle's operating mode to hybrid mode before the carbon canister reaches saturation to achieve timely desorption of the carbon canister. This effectively avoids the occurrence of fuel vapor leakage caused by carbon canister overload, Ensure that the carbon canister can be in effective working condition for a long time.

A simple understanding is that if an EV is driven for a long time, it will start the engine briefly in about 6 days, while generating electricity, lubricating, and desorbing, which is both legal and reasonable.

Data shows that BYD DM-i has solved the technical problem of free gasoline vapor desorption in PHEV atmospheric fuel tanks, achieving "one quiet and three gains": one quiet, excellent NVH, which can achieve seamless and fast gasoline vapor desorption during driving; Three benefits, achieving fast desorption, efficient power generation, and engine maintenance.

I believe that under the premise of legality and compliance, in the context of the rise of domestic brands and the encirclement of numerous foreign brands, it may be the top priority for Chinese brands to unanimously expand the market to the outside world!