Lloyd's Register (LR) has recently granted Approval in Principle (AiP) to HD Korea Shipbuilding & Offshore Engineering (HD KSOE) for their innovative vacuum-insulated large-scale liquid hydrogen (LH₂) tank system. This groundbreaking system addresses crucial challenges associated with hydrogen storage and transportation in the maritime industry. The successful testing of a large-scale vacuum chamber for this AiP marked a significant milestone as the world's first technical validation of large-scale LH₂ tank insulation design. One of the main obstacles in using hydrogen in the maritime sector is the scalability of liquefied hydrogen storage and the efficient transportation of the fuel. Storing liquid hydrogen at extremely low temperatures while minimizing boil-off gas necessitates vacuum-insulated tanks similar to thermos flasks. However, implementing this technology on a large scale in ships has been technically unproven. For instance, NASA's largest existing LH₂ tank has a capacity of 5,000 m³, whereas ship-based applications may require tanks over four times larger. HD KSOE's vacuum system offers an innovative solution that significantly reduces the time needed to achieve a vacuum in large tanks, overcoming a critical barrier to the widespread adoption of hydrogen in ship-based applications. The development and validation of this system involved collaboration with key industry players, including Woodside Energy, Mitsui OSK Lines (MOL), and Hyundai Glovis. The system's test results were shared with these companies and international classification societies like LR, which confirmed a notable reduction in vacuum time in shipyards. This achievement underscores the importance of industry collaboration in advancing hydrogen technologies for maritime use, highlighting the potential for sustainable and innovative solutions to meet the evolving needs of the maritime sector in a rapidly changing energy landscape.