Google Capital has been writing big checks to late-stage tech start-ups since 2013 and has now backed 11 companies in areas including web finance, online education and big data, according to its web site.
The search giant's investing arm has been cagey about the purpose of its involvement in those companies, and while potential financial gains are part of the allure, Google's balance sheet is so big that any returns aren't likely to make a dent.
Read MoreHas Google lost its mojo?
Online loan provider LendingClub, which was one of Google Capital's first investments, announced Thursday that the two companies are working together to extend credit to a wider swath of small businesses. Google has 10,000 customers using its business tools, like web-based documents and spreadsheets, Gmail and its cloud-hosting technology.
Companies in Google's network will be able to apply for credit on LendingClub's platform, and if accepted, Google can then purchase the loans, thus becoming the lender. LendingClub, which sold shares to the public in December, issued about $1.2 billion in loans last quarter, mostly to consumers who use the service to consolidate debt at lower rates than they can get from credit cards.
For Google partners, two-year loans, serviced by LendingClub, will start at 5-percent interest and the rate can fluctuate up or down in the second year based on performance. Loans will be capped at $600,000, or about twice as high as LendingClub's standard business loan.
"It's a way for Google partners to access more capital and cheaper capital than what they would get from a bank or even from us," said Renaud Laplanche, LendingClub's founder and chief executive officer, in an interview. Google has "the opportunity to earn more interest on loans than what Google Treasury is earning with the tens of billions of cash they have."
A spokesperson for Mountain View, Calif.-based Google declined to comment beyond the announcement.