It is narrated from Hazrat Abu Musa (may Allah be pleased with him) that the Noble Prophet (peace and blessings be upon him) used to give rewards in the battles.
Hadith Referenceمسند احمد / تتمہ مُسْنَدِ الْكُوفِيِّينَ / 19601
Hadith Gradingحکم دارالسلام:صحيح لغيره، وهذا إسناد ضعيف لضعف عبدالعزيز بن عبيدالله