Lithium-ion Battery Arrangements Planned for New Japanese Submarines

Submarine Matters looks at Japanese submarines in detail with periodic updates (for example on August 26, 2016). The following is the latest update followed by the SORYU TABLE. The Japanese Navy (JMSDF) is highly likely to be the first Navy to use Lithium-ion Batteries (LIBs) on its diesel-electric submarines. At the same time these new submarines, known as Soryu Mark 2s, will not use the existing Stirling AIP systems.

The first Soryu Mark 2 (with LIBs, no AIP) carries Soryu program number “27SS” (see table below). Construction of 27SS at the MHI shipyard in Kobe began in 2015. 27SS might be launched this year (2017) (with LIBs being inserted after launch?). With such a new battery technology for submarine use 27SS will undergo many more trials/tests and exercises than usual, It may be commissioned by 2020.

The arrangement of batteries, including LIBs, has many implications and affects, influencing:

-  a submarine’s overall arrangement of all the other large internal items (fuel tanks, command center 

   location, diesel placement etc)

-  balance/buoyancy of the submarine

-  ease of removing old LIBs and placing in new ones

-  electronic control of function and performance of the 100s of batteries used

-  particularly avoiding runaway heat buildup in battery groups

-  emergency measures

-  minimising the batteries' electromagnetic emissions out of the sides and bottom of the submarine

   (with implications for indiscretion)

Some interesting new information on 27SS’s LIB arrangement and many other details appeared in January 2017 on wispywood2344’s blog at http://blog.livedoor.jp/wispywood2344/archives/2017-01.html. The information is by way of a Japanese Freedom of Information request possibly made by wispywood2344.

After viewing http://blog.livedoor.jp/wispywood2344/archives/2017-01.htmlan Anonymous commented:

According to wispywood2344, 27SS shall be equipped with 2 battery module groups.

A.  Each group consists of 16 rows x 20 columns, adding up to 320 batteries per group x 2 totals 640

      batteries.

But, Anonymous thinks 27SS shall be equipped 2 possible different arrangements for the battery module groups.

B.  The 2 battery module groups, will consist of 12 rows x 28 columns, adding up to 336 batteries x 2

      totalling 672 batteries, OR

C.  12 rows x 24 columns, adding up to 288 batteries x 2 totalling 576 batteries.

By placing SORYU in the top left Search Box you will notice a wealth of information on Japanese submarines kindly provided to Submarine Matters.