Plaid, a unicorn that helps connect consumers’ bank accounts to financial applications, has raised a $425 million Series D, it announced this morning. TechCrunch understands that the new capital infusion, led by Altimeter Capital, values the company at around $13.4 billion. It is not surprising that Plaid, a former takeover target for consumer credit giant Visa, is raising more capital. After its $5.3 billion sale to the larger company fell through this January, it became clear that Plaid would chart its own future, sans a corporate parent. When the Visa-Plaid…