What is the ruling on a wife working in a bank without helping her husband with household expenses, knowing that his income is sufficient?

It is permissible for a woman to work in a bank that operates according to the provisions and regulations of Sharia (definition), with the husband's permission or by stipulating it in the contract. She is not obligated to spend from her salary on the household unless the husband stipulates it. As for working in an interest-based (riba) bank, it is absolutely impermissible.