Ex-Hydro-Québec researcher, accused of spying for China, defends reputation at trial

Yuesheng Wang arrives for his espionage trial at the Longueuil courthouse in Longueuil, Que., on Monday, Oct. 6, 2025. (Christinne Muschi/The Canadian Press)

Yuesheng Wang, a former researcher with Quebec’s hydro utility on trial for allegedly spying on behalf of China, testified on Tuesday that his first paycheck came six weeks after he started the job because he wasn’t shown how to complete payroll forms.

The 38-year-old has pleaded not guilty to economic espionage under Canada’s Security of Information Act. Wang is accused of sharing confidential research from Hydro-Québec with Chinese entities for the commercialization of battery technologies.

On the witness stand at his trial on Montreal’s South Shore, Wang described himself as a confused newcomer to the company in 2016, who spoke neither French nor English and didn’t receive proper training, particularly about the utility’s code of ethics or workplace standards.

“In my memory there was nothing, because I was there a month and I even don’t know how to fill company forms,” Wang said about the support given to him at Hydro-Québec’s research institute — Center of Excellence in Transportation Electrification and Energy Storage.

Testifying in Mandarin through an interpreter, he told Quebec court Judge Jean-Philippe Marcoux, “At that time, I had a language barrier, I couldn’t speak English or French and I got the impression people didn’t really want to talk to me.”

Wang, a Chinese national and resident of Candiac, Que., south of Montreal, has denied spying for China. He noted on Tuesday he was no longer a member of the Chinese Communist Party and only had been a member during his university days.

The trial has heard that the publication of an academic paper in March 2022, which included Wang’s name, set off an internal probe at the utility that would later be transferred to the RCMP.

The Crown also alleges that Wang, while he was working at Hydro-Québec, submitted applications to Chinese universities under the framework of the Thousand Talents program, a recruitment tool used by the Chinese government to attract foreign-trained scientists to return to work in China. In the applications, Wang allegedly committed to assisting Chinese entities in commercializing battery technologies related to confidential research domains at Hydro-Québec.

Wang worked from 2016 to 2022 at Hydro-Québec’s research institute, located in Varennes, Que., which looks into advanced battery technologies and energy storage systems.

He says the information he shared in his applications to the Chinese program was open source and came from his lengthy academic career researching sodium-ion batteries before he moved to Quebec. Research on sodium-ion batteries was “very hot” during his PhD studies, he said, but the subject has been researched by scientists for more than 40 years. His academic research into sodium batteries resulted in at least 400 citations and nine patents in China, he added.

Wang told the court that his decision to come to Quebec was influenced mainly by the chance to work with Dr. Karim Zaghib, an internationally renowned academic and retired Hydro-Québec official. Zaghib was launching the research institute when Wang was hired.

Wang got the job despite not speaking any French and limited English. The accused recounted an incident in 2017 over a snafu in the construction of a battery that prevented him from publishing a paper. “For a researcher like me, if I sent the results of my work with this kind of mistake it would ruin my reputation and that of Hydro-Quebec,” Wang testified.

“Then people started to talk between them and they said I was a very difficult person and no one wants to work with me anymore.”

Earlier during trial, the prosecution presented a video of Wang’s seven-hour interrogation by an RCMP officer over the various documents, drawings and other academic work Wang had emailed to himself without Hydro-Québec’s consent.

Witnesses from Hydro-Québec have testified that intellectual property that is created at the center of excellence belongs to the utility.

Defence lawyers say Wang will comment on the Crown’s evidence on Wednesday.

Wang is also on trial on four other charges: fraudulently using a computer, breach of trust, committing preparatory acts on behalf of a foreign entity and informing that entity — the People’s Republic of China — of his intentions. Another charge of fraudulently obtaining a trade secret was withdrawn.

This report by The Canadian Press was first published Nov. 4, 2025.

By Sidhartha Banerjee, The Canadian Press