It is narrated from Urwah bin al-Zubayr (may Allah have mercy on him) that on the day of Badr the Messenger of Allah (peace and blessings be upon him) made the battle-cry of the Muhajirun "Ya Bani Abd al-Rahman!" (O sons of Abd al-Rahman!), the battle-cry of the Khazraj "Ya Bani Abdillah!" (O sons of Abdullah!), and the battle-cry of the Aws "Ya Bani Ubaydillah!" (O sons of Ubaydullah!), and he named his cavalry "Ya Khayl Allah!" (O horsemen of Allah!).
This is mursal, and it has been narrated with a connected chain.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قسم الفيء والغنيمة / 13050