Michelle Young, 49, estimated that husband Scot Young, 51, was worth "a few billion at least" and said "there was a vast fortune hidden".
She told Mr Justice Moor at a hearing in the Family Division of the High Court in London that she would settle for £300 million plus legal expenses.
Mr Young has yet to give evidence but has previously told judges he is penniless and bankrupt, a victim of financial meltdown and hopelessly insolvent.
He disputed Mrs Young's allegations and at one point asked the judge if her "ranting" was allowed.
Mrs Young told the court of her lifestyle when she was living with Mr Young.
She said: "We had vast estates. We had staff. We had a very luxury lifestyle."
She added that Mr Young would spend up to £5000 for a restaurant meal, and that they had gone to a Raymond Blanc restaurant twice a week.
She also said Mr Young had paid £2m to £4m for "a flash gin-palace, Sunseeker-type boat"; that she had jewellery which Mr Young had said cost a million pounds; and that they went on three to four foreign holidays a year, staying in presidential suites.
She told the judge: "We had a chandelier in our drawing room. The other chandelier sits in the White House. They were valuable assets."
She said they had lived in Belgravia, central London, for three or four years and in Miami, Florida, where they owned three Porsche cars.
She said they had moved house a number of times and the profit on one house was £10 million.
However, Mrs Young said Mr Young, who was born in Dundee, was incredibly secretive about finance.
She said: "There was a vast fortune hidden. He used offshore vehicles and many advisers and accountants to layer these assets."
Mrs Young said she wanted a £25m house and to live in Belgravia. She said: "It's a nice area. It's very safe. This case is not about means. It's about quality."
The judge has heard that the Youngs, who both live in London and have two daughters, separated in 2006 after starting a relationship in 1989.
They have been fighting over money for several years.
Mrs Young was asked by a lawyer how much she would settle for. She replied "Three hundred million plus all my legal expenses. I think he is worth a few billion at least."
Mrs Young said Mr Young was secretive about finance.
She said: "He was constantly on the phone to his high-profile friends and advisers talking about multimillion-pound deals he was involved with," she said.
"If I heard it ... he would quickly run off ... or jump out of the Phantom or Ferrari so I couldn't hear. I wasn't made aware very much regarding the business side."
In January, Mr Justice Moor imposed a six-month prison term on Mr Young after concluding he had failed to provide financial information to his wife during preliminary stages of litigation and was in contempt of court.
The judge said Mr Young's failures to obey court orders had been flagrant and deliberate.
He is to make a decision about how much Mr Young is worth after hearing evidence in the next few weeks. The trial, which continues today, is being staged in private but Mr Justice Moor has given permission for it to be reported.