Margalit was born on June 4,1926 in Old Tel-Aviv, to her parents Avraham and Leah Nadav. She studied at the Neve-Tsedek School for Girls. When she was 14, she joined Beitar. In 1944, in the midst of WWII, she joined the British Army and served in Egypt at the ATS Females Unit. There she met Lehi member Ehud, who recruited her to Lehi. From that day on, she made efforts to be discharged so she could join her fighting comrades in Israel. In 1945 she returned to Israel and resumed full Lehi activities, bearing the name Bat-Zion. First she was integrated in the operations division, and afterwards she was Instructing at the youth division. After a while she was sent to the Samaria region, to organise the youth in the settlements. Following establishment of the State, she joined her comrades in the Lehi Battalion of the IDF, where she served during the entire duration of the War of Independence.
In 1949 she married Dov Bentov, a fellow Lehi member whose nom-de- guerre was Yoram. They resided in Tel-Aviv and had their three children: Avigdor, Efrat and Tomer-Yair plus five grandchildren.
In 1972 the couple decided to move to Kiryat-Arba (Hebron), out of their conviction that this was the way to realizing their beliefs.
After five years, Margalit returned to Tel-Aviv. In 1979 she began working in the Executive Department of the Leumi Bank, and worked there until June 1989.