I found this article from 2013 when Maryland came to the Big Ten.
Mary Ann Rankin The university’s move to the Big Ten will bring new collaborations on the academic front, many of them out of reach for members of the ACC, officials said. Beginning July 1, 2013…
dbknews.com
From what I can tell, schools don't necessarily share funding (may sub contract work out). But the collaboration and sharing can lead to the following. This is where the
"sharing and working together on research" comes about. You have the ability to reach out to peers in other Big Ten universities who might have a wider and deeper knowledge in the area you are trying to get research funding for (widen and deeper your own abilities in the process).
Although the CIC does not provide research grants and will not contribute to a direct source of research funding, university Research Vice President Pat O’Shea said membership will allow for greater research collaboration between universities, which often makes it easier to obtain larger grants.
It is hard to predict how much CIC membership will increase research funding, O’Shea said, but the coalition will lead to more collaboration outside of the local area and give the university a competitive edge.
“Ultimately, it will increase the research funding and the quality of the scholarship,” he said. “We’ll be playing research with higher quality colleagues. It will up our game.”
Michigan State University President Lou Anna Simon agreed, saying the CIC allows for collaboration in both research and leadership among the institutions.
“It allows greater collaboration, which has led to greater research opportunities,” she said.
