He said the move would mean 360,000 firms offering on-the-job training.
The Business Secretary said companies would be offered exemptions from National Insurance and apprenticeship grants as extra incentives.
The other main parties have already made pledges to create more apprenticeships for young people.
Labour says it would guarantee apprenticeships for every school leaver in England who “gets the grades” by 2020, while the Conservatives have promised three million new apprentices under a Tory government.
David Cameron said earlier this month the coalition government had created 2.2 million apprenticeships since 2010.
Mr Cable said: “The world is changing at an accelerated rate and we need to equip our young people with the skills they need for the future, to ensure they can compete in a global marketplace, in ever- changing technologies and the digital economy.
“That is why the Liberal Democrats will double the number of employers providing apprenticeships over the next five years and create more apprenticeship starts per year than Germany.
“To achieve these objectives requires significant investment in skills by both government and the private sector. As we grow our economy, the Liberal Democrats believe we must enhance adult skills training and our further education colleges.”