German billionaire Berthold Albrecht, heir to the Aldi supermarket chain and one of Germany's richest men, has died aged 58, his family has announced.

Together with his brother Theo Jr, Albrecht's fortune was estimated at €13.7bn, according to Forbes.

That placed them at 32 in the list of Forbes billionaires and second for Germany.

"Berthold was a fighter, and full of hope to the end," his wife, Babette, wrote in a full-page notice published in several German newspapers.

The notice from the notoriously reclusive family said that the funeral had taken place in November, but it did not give further details of the circumstances of his death.

Berthold was the son of Aldi co-founder Theo Albrecht, who died at the age of 88 in July 2010.

After the Second World War, Theo and his brother Karl turned the small grocery store their mother operated in Essen into one of the nation's largest food retail chains, with a focus on a limited range of goods at bargain prices.

Aldi was split into two divisions covering north and south Germany in 1960. Theo took the north and Karl the south.

Karl, aged 92, is classified by Forbes as the richest man in Germany with a fortune of €19.6bn.

The Aldi empire, which has estimated worldwide annual turnover of about €50bn, also owns the Trader Joe's grocery chain in the United States.

In Europe it competes with the likes of Tesco, Carrefour and Metro.

Berthold worked on the board of directors at Aldi North.