According to industry sources on Jan. 1, Hanwha Ocean is set to make a pioneering move by installing lithium-ion batteries in a 3,000-ton class submarine (KSS-III Batch-II), a first in South Korea's submarine history. Traditionally, submarines operate by using diesel engines to charge batteries, which then power the propulsion motors. Previously, lead-acid batteries were widely used due to their lower manufacturing cost. However, the next-generation submarine from Hanwha Ocean, set to begin construction in 2025 and expected to be delivered in 2028, will utilize lithium-ion batteries.
Lead-acid batteries, while cheaper to produce, have shorter lifespans and lower energy density. They also produce hydrogen gas during charging, posing risks of overheating and explosion, which necessitates the installation of various auxiliary systems such as ventilation fans for gas removal.
Lithium-ion batteries offer a larger capacity within the same volume compared to lead-acid batteries and do not produce gas during charging, reducing the need for auxiliary equipment and frequent maintenance. They also have shorter charging times. Hanwha Ocean’s adoption of these batteries is expected to significantly enhance the performance of its Air Independent Propulsion (AIP) system, a technology that allows submarines to generate electricity and propel themselves underwater without external air intake.
According to Hanwha Ocean, the KSS-III Batch-II submarine, with its lithium-ion batteries, will be able to operate submerged more than three times longer than the lead-acid battery-equipped KSS-III Batch-I. This is considered among the world’s longest for non-nuclear powered diesel submarines. The KSS-III Batch-I’s maximum submerged period is known to be around 2-3 weeks.
The lithium-ion batteries for these advanced submarines will be produced in-house by the Hanwha Group. The equipment will be handled by Hanwha Momentum, a division that manufactures various secondary battery production equipment, while Hanwha Aerospace will take charge of design and manufacturing. Hanwha Group, which broadly conducts defense business from the ground to space, aims to expand its secondary battery business for defense purposes, led by Hanwha Aerospace.
In addition to this development, Hanwha Ocean, leveraging its submarine technology expertise, is also pursuing a contract for Poland’s submarine project, known as the ORKA Project. This project aims to acquire four new submarines with a total budget of 2.25 billion euros (US$2.49 billion), focusing on capabilities like over 30 days of operational endurance, a diving depth of over 200 meters, and the ability to strike ground, surface, and underwater targets with torpedoes and mines, including supporting special operations. Hanwha Ocean’s KSS-III class submarines are considered an ideal model for meeting all of Poland’s requirements.