Maritime self-defense force of Japan on 5 March 2020 adopted in its composition of diesel-electric submarine “Yelling” of the “Soryu”. As noted bmpd, the world’s first military submarine with Li-ion rather than the traditional lead-acid batteries.
Diesel-electric submarine batteries are needed for stealthy movement under water when starting the diesel engine to power the undercarriage motors are undesirable or impossible. Traditional lead-acid batteries cannot provide the large running time and long charging.
The decision to use lithium-ion batteries on submarines type “litter” was made for several reasons. Firstly, these batteries have substantially higher capacity than lead-acid. At low speeds the range of underwater travel of the submarine on lithium-ion batteries is comparable to the range on lead-acid batteries and the Stirling engine.
For this reason, Japanese designers have decided to abandon the installation of the Stirling engine in a submarine, powered by lithium-ion batteries. Because of this inside the submarine managed to free some space.
Secondly, at high speeds the range of the vehicle with lithium-ion batteries is considerably greater than this figure when using lead-acid batteries.
Thirdly, lithium-ion batteries can be recharged using high currents than the charging of lead-acid batteries. This means that on a full charge Li-ion batteries must be significantly less time.
Submerged displacement of the submarine “Yelling” is 4.2 thousand tons with a length of 84 meters and width of 9.1 meters. The ship can reach the speed of 20 knots. “Yelling” was the 11th submarine, built in the style of “litter”. Ships of this type built before equipped with lead-acid batteries and Stirling engines.
In March of 2021 Maritime self-defense force of Japan intend to take part in a 12-th submarine of the “Soryu” — “Lay”. This ship, launched in November last year, is also equipped with lithium-ion batteries.
In the middle of last year the Japanese Corporation Mitsubishi Heavy Industries have started to develop a diesel-electric submarine of the new generation. The work is carried out in the framework of the project 29SS. New submarines in the future it is planned to gradually replace diesel-electric submarines of type “litter”, adopted in 2009.