The Taigei class is equipped with a large amount of lithium-ion batteries, as is the case with the eleventh and twelfth submarines of the Sōryū class (Ōryū and Tōryū), making it possible for the submersible to travel longer and at higher speeds under water than conventional diesel-electric submarines.

In 2004, an evaluation was made on researching next-generation submarine systems based on capability requirements: dive speed, stealth, etc.

The research involved utilizing simulation technologies to optimize the most efficient design for the submarine and analyze its cost-effectiveness.

The project reflected that the submarines would be introduced in the 2020s and that the research is conducted between 2005 and 2008, while in-house testing occurs between 2007 and 2009.

The second projects aimed to develop new AIP system to extend underwater sustainability for future submarines.

Likewise, the new AIP systems will allow the submarines to expand their operational areas, including responding in shallow waters.

A secondary purpose of this buffer research is to protect and mitigate against shock delivered from outside coming into the submarine.

However, both engines were deemed to output below required performance and thus the development of a new power generation system was initiated.

[15][16] In 2016, proposed research on new hull design to reduce fluid noise and a new sonar system to cope with the quietness of future foreign ships and submarines were evaluated.

The silent drive system is used to further reduce the noise emitted from the submarine in response to improvements made in sonar technology by other countries.

[28] Kawasaki Heavy Industries (KHI) received a research and development (R&D) contract from the Ministry of Defense on December 29, 2023 to design a new diesel-electric submarine (SSK) class.