Not looking for quite a direct biography since there isn't too much info on the Charles but perhaps a book talking about the build up to the Carolingian dynasty that references Charles Martel. I can't seem to find a good one anywhere
Nothing that only focuses on Charles Martel by himself, but
McKitterick, Rosamond. Charlemagne: The Formation of a European Identity. Cambridge University Press, 2008.
McKitterick, Rosamond. The Early Middle Ages: Europe 400-1000. The Short Oxford History of Europe. Oxford ; New York: Oxford University Press, 2001.