The Kawasaki Heavy Industries has officially put on water Taggeii-Class Sixth Japanese submarine as part of a Kobe celebration. The name of the new ship JS Sogei (SS 518)and uses the latest lithium ion battery technology.
The event was held at Kawasaki’s Kobei shipyard-in this city considered to be the cradle of Japanese submarine construction-and was attended by representatives of Japanese Navy Self-Defense Forces (JMSDF).
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The name “Sogei” (そうげい) means “big and brilliant whale”, following a Taggeii-Class tradition to supply their ships with names related to the sea and whales.
According to JMSDF, JS Sogei is scheduled to be officially launched in March 2027, which will further strengthen Japan’s submarine capabilities in the midst of fleet modernization in the Indo-Chendes-Ocean region.
The construction of Sogei began on March 28, 2023. The submarine is designed with a drive system that uses lithium ion batteries-this technology replaces the traditional air-independent (AIP) system-which provides longer dive time, lower noise and simpler maintenance.
JS Sogei, 3,000 tons and 84 meters long, can reach up to 18 knots under water and 13 knots on the surface. Its main weaponry consists of six 533 mm torpedo tubes compatible with Type 18 torpedoes and Harpoon anti-ship missiles.
The submarine is also fitted with the new 12ssm-is also with cruiser deposits recently developed to increase the offensive range of the Japanese Navy.
A TaggeiiClass is a technological milestone for Japan, as it is the first class in the world to develop specifically for operation with lithium ion batteries. This innovation elevates the Japanese fleet as one of the most advanced in the quiet drive and energy efficiency.
In March 2025, the JMSDF had already served the fourth submarine belonging to the same class, JS Raigeiwhich is currently stationed on Kure’s base. Unlike previous models, Raigei was equipped with Kawasaki 12V2531 diesel engines and the modern ZQQ-8 sonar system developed by OKI Electric Industries, indicating the continuous technological development of the class.
Source and pictures: Japanese Ministry of Defense – Maritime Volunteer Defense Forces @Jmsdf_pao_. This content was made with artificial intelligence and was checked by the editorial team.
