It is narrated from Abu Salamah (may Allah have mercy on him): I came to Sayyidah Aishah (may Allah be pleased with her) and said: "O mother, tell me about the (night) prayer of the Messenger of Allah (peace and blessings be upon him)." She said: "The night prayer of the Messenger of Allah (peace and blessings be upon him), whether in Ramadan or in other months, was thirteen rak'ahs, including the two (sunnah) rak'ahs of Fajr." I said: "Tell me about his fasting." She said: "He (peace and blessings be upon him) would fast (so continuously) that we would say: Now perhaps he (peace and blessings be upon him) will not stop fasting; and he would leave off fasting (for so long) that we would begin to say: Now perhaps he (peace and blessings be upon him) will not fast. I never saw the Messenger of Allah (peace and blessings be upon him) fasting more in any month than in Sha'ban. He (peace and blessings be upon him) used to fast almost the whole of Sha'ban; that is, he (peace and blessings be upon him) used to fast the month of Sha'ban except for a few days."
Hadith Referenceمسند أبي يعلى الموصلي / مسند عائشة / 4860