South Korean Lithium-ion Batteries for Submarine use Estimates

Following Submarine Matters’ article of November 5, 2019 there is still little published information on South Korea’s (SK’s) lithium-ion batteries (LIBs) for submarine use. To partly fill the gap Anonymous has provided likely estimates and links below.

Significant estimates for SK LIB include dimensions of battery modules and total price of the SK LIBs producer SAMSUG SDI battery modules for the DSME 2000 and KSS-III Batch 2 submarines. This is based on the video and other data - see [1] and [2] below.

DSME 2000 and KSS-III Batch 2 submarines will be equipped with the same battery tray, but, the number and total energy of battery trays will be different. 2,200 ton DSME 2000s will have 128 trays producing total energy of 8.6 MWh. While 3,700 ton (submerged)  KSS-III Batch 2s will have 192 trays producing 12.9 MWh).

SK LIBs price per unit power [measured in US$/Wh] is quite low and may be cheaper than lead-acid batteries (LABs). That is a ratio of US$0.3 for a SAMSUNG SDI LIB cell compared to US$0.69 for a Japanese GS-YUASA LAB cell. Meanwhile a Japanese GS-YUASA LIB cell (developed for Japan’s Soryu subs) may cost US$1.61. From the viewpoint of cost, DSME 2000 may be serious export competition to the TKMS Type 214, SAAB A26 and Naval Group Scorpene.

(above and below) LIBs in yellow can be seen on these future DSME 2000 submarine models. (Above courtesy Naval News and Below courtesy IHS Markit/M Boruah )

[1] Assumptions

As the LIBs market for submarines is extremely small, SAMSUM SDI will use existing battery modules and cells of proven reliability.

Use a standard battery trays in future DSME 2000s and KSS-III Batch 2s reduces costs.

Battery trays arrangements in the battery section of DSME 2000s is 8 rows x 8 columns and in the KSS-III Batch 2s it is 12 rows x 8 columns. Such arrangements minimize stray magnetic fields.

Dimensions (W x D x H in mm) of battery trays are from 500 x 300 x 900 to around 600 x 400 x 1200.

A battery tray consists of 8 battery modules. A battery module in turn consists of 12 cells.

The price per submarine of  LABs is around US$137 million and if it were to have LIBs the price currently is around US$780 million (or 85 Billion Japanese Yen). Cost of LIBs is currently very high as they are new, rare and still include high development costs portions in their overall price. Costs would also include extensive computer control for safety. But LIBs have many advantages (longer lasting between recharges, faster and deeper charging by diesel engines, and SK LIBs will have about twice as many cycles (4,000) compared to LABs (2,000). The price of battery trays are more expensive than the sum of their cells.

[2] Possible battery module and cell

A SAMSUNG SDI Battery module used for submarine may be designated M8994 E2. See the specifications and small diagram of the M8994 E2, under the subheading “2016 module” by scrolling about half way down http://www.samsungsdi.com/upload/ess_brochure/Samsung%20SDI%20brochure_EN.pdf 

Note Energy quoted is 8.39kWh, Dimensions 370 x 588 x 160mm, weight <60kg span="">.

Does the SAMSUNG SDI LIBs for submarine use the chemical formula Lithium Nickel Manganese Cobalt Oxide (LiNiMnCoO2) abbreviated NMC? Such a cell is the SAMSUNG 94 Ah. see https://pushevs.com/2017/02/20/details-samsung-sdi-94-ah-battery-cell/ where Energy is 350Wh, Dimensions 173x125x45mm, weight 2kg, price 162.69€,

Scrolling a fifth way down https://batteryuniversity.com/learn/article/types_of_lithium_ion at “Figure 7: Snapshot of NMC” you will see NMC has a good balance of characteristics, ie: Specific Energy, Specific Power, Safety, Performance, Life span and Cost.

Battery tray. Estimated specification of tray consisted of eight layers of M8994 E2 with dimensions (W x D x H in mm) = 588 x 370 x 1280.

Calculation of energy of KSS-III Batch 2 is 8.39kWh (energy of M8994 E2) x 8 (layers of M8994 E2 in a battery tray) x (12 x 8) (row and column of battery tray) x 2 (battery sections) = 12.88MWh.

DSME, SAMSUNG SDI, GS-YUASA and any other readers are invited to correct, fill-in and thereby expand public knowledge on specifications of LIBs for submarines and comparison with LABs.