No, B1/B2 is not the right visa type in your case. The university will "benefit" from this, even if it will be at a later time.
You also will benefit if any research activity you’ll conduct will use any of the institute services/equipment. Independent means you will be independent, no help from a US based institute. It’s not only about getting paid, that’s an addition to the "independent" part.
My sources? who will be better than the US universities who must have faced this countless times, so they have done the homework for you. They all state that a J-1 visa is required/preferred.
Here are a few links from various US based universities that explain this in details for people in your situation:
https://isss.ucsc.edu/departments/othervisas/bvisa.html
These visits can be short in duration, the visitor may not be paid, and they will not have a formal appointment at the university. However, if the university is benefiting from the visit, if equipment and facilities used are owned or operated by the university, the contents of the visit and/or research activity undertaken might result in the form of published work, patent or discovery at a later date, and/or the visitor is involved in a formally structured program, use of B1/B2/WB/WT visa will contradict U.S. Department of State guidelines….
https://ap.washington.edu/ahr/visas/b-visa/#business
Foreign nationals coming to the UW to perform research must hold a visa appropriate to the activity. Generally, this requires University sponsorship for a J-1 or H-1B visa. It is not lawful for foreign nationals to perform research in the United States on a visitor (B-1 or B-2) visa or visa-waiver, even for short periods, unless the research is strictly “independent” (e.g., book research in the library) and provides no benefit to a US institution.
http://isss.gsu.edu/administrators/using-the-b1b2-visitors-visa-category/
NOTE: The B-1 business visitor category is not appropriate for visitors engaging in active in-lab research or collaborative activities that will benefit Georgia State in any way. Visitors involved in exchange programs, formal collaboration between institutions, or joint research projects from which Georgia State will benefit should use the J-1 Exchange Visitor visa.
Credit:stackoverflow.com‘