Lea Nikelsberg was born in 1918 in Zhitomir, Ukraine. Her family immigrated to British-administered Palestine in 1920. She began studying with painter Chaim Gliksberg in Tel Aviv in 1935, later studying with Yechezkel Streichman and Avigdor Stematsky.
Nikel's style was a form of expressionistic abstraction sometimes called lyrical abstraction. She painted with a brusque, generous touch and favored high-keyed colors. She was known for compositions consisting of rough-edged blocks of color and scribbly, calligraphic lines that together conveyed a sense of imaginative excitement and urgent sensuousness.
Nikel held her first solo exhibition at Chemerinsky Art Gallery in Tel Aviv and her first solo show in Paris at Galerie Colette Allendy in 1957. She took part in numerous international group exhibitions, including the Venice Biennale in 1964. The Tel Aviv Museum of Art organized a retrospective exhibition of her paintings in 2005. Nikel continued to paint until just a few days before her death in September 2005.