There's no limit to the number of Team Members that can be on a Team in Connect Space.
To add a Team Member:
1) Click on your profile icon in the top right corner and select Manage Team from the dropdown.
2) Click the Add Member button.
3) Enter the new member's email address and select their Permissions.
4) Click the Add Member button to send the invitation.
To join the team, the recipient must click Accept Invitation in the invitation email.