Poster submarine Taigei class

The Taigei class is a series of diesel-electric submarines in service with the Japanese Navy since 2022, developed from the Sōryū class. Designed to optimize the use of lithium-ion batteries, tested on the last two Sōryū class submarines, these submarines benefit from technical improvements. For example, the mass is slightly longer to accommodate more masts and improve hydrodynamics. They also have better sound insulation, new fiber optic sonars, and spaces adapted for female personnel.

The first submarine of this class, the JS Taigei, cost approximately 80 billion yen (758.7 million dollars) and serves as a test platform for the Japanese Navy rather than an operational unit. This choice marks a difference from the previous planned evolutions, which were more ambitious. The Taigei class therefore retains dimensions close to the Sōryū class, with a slight gain in displacement (2,947 tonnes on the surface, or around 100 tonnes more).