If I limit myself to indeed scarce English literature on the subject, both books and papers, a quick glance gives;

(1) John P. Spielman (1977). Leopold I of Austria. Rutgers University Press.

(2) Charles W. Ingrao (2000). The Habsburg Monarchy, 1618–1815. Cambridge University press.

(3) Joachim Whaley (2011). Germany and the Holy Roman Empire: Volume II: The Peace of Westphalia to the Dissolution of the Reich, 1648-1806. Oxford University press. ( See chapter "Reconstruction and Resurgence, 1648–1705: the Reich Under Ferdinand III And Leopold I" )

(4) Frey, L., & Frey, M. (1978). A Question of Empire: Leopold I and the War of Spanish Succession, 1701–1705. Austrian History Yearbook, 14, 56-73.

(5) Frey, L., & Frey, M. (1978). The Latter Years of Leopold I and His Court, 1700-1705: A Pernicious Factionalism. The Historian, 40(3), 479–491.

(6) Bérenger J. (1990) The Austrian Lands: Habsburg Absolutism under Leopold I. In: Miller J. (eds) Absolutism in Seventeenth-Century Europe. Problems in Focus Series. Palgrave, London.

...

Although all these works (or sections therein) are not biographical, even the first one pays little attention to his upbrining, early education and other similar topics that are usual in biographical works. For this, literature in German is probably needed.