# Electrification in Maritime Vessels: Reviewing Storage Solutions and Long-Term Energy Management
## 4 Maritime Battery Projects
### Battery Projects of Hybrid and All-Electrical Vessels in the World  
Lithium-ion (Li-ion) batteries are the most widely used energy storage systems in maritime applications, primarily due to their high energy density, long cycle life, and relatively fast charging capabilities. These characteristics make them particularly well-suited for both hybrid and fully electric propulsion systems. Their compact size and performance efficiency contribute to their dominance in the industry. Lithium iron phosphate (LiFePO\({}_{\textbf{4}}\)) batteries, a subtype of lithium-ion technology, have gained popularity for their exceptional safety, thermal stability, and long service life. While they offer slightly lower energy density than other lithium-ion chemistries, their resistance to overheating and thermal runaway makes them a preferred choice for applications where safety is paramount, such as passenger vessels or ferries. Lead-acid batteries, though considered a more traditional technology, continue to be used in auxiliary power systems and emergency backup applications. Despite being heavier and less energy-dense compared to lithium-based alternatives, their lower initial cost and proven reliability make them a viable option in certain contexts, particularly where cost-effectiveness is a key consideration. Nickel-based batteries, including nickel-cadmium (NiCd) and nickel-metal hydride (NiMH), are utilized in specific maritime applications that demand durability and performance under extreme environmental conditions. Their ability to function efficiently across a wide range of temperatures, combined with a robust cycle life, makes them suitable for specialized vessels and equipment operating in harsh climates.  
Hybrid marine vessels offer a more environmentally friendly and energy-efficient transportation option by using various types of batteries. Table 4 indicates the variety and features of hybrid marine vessels available in various countries. The table allows us to compare the battery types, production years, passenger capacities, vehicle carrying capabilities, speeds, and sizes of these vehicles. The differences in speed and size in the table show that these vehicles depend on the purposes and routes for which they are used. Ships used for tourist tours generally have slow speeds and large sizes, indicating the capacity to carry more passengers, while faster and smaller ships are especially suitable for short-distance voyages. Thus, it reflects the efforts of various countries to develop and use these environmentally friendly vessels. This can be seen as a step towards the evolution of maritime transport towards a sustainable future.  
Table 5 presents the battery specifications of various electric ferries. The types and capacities of batteries used on ferries vary significantly. For example, large ferries such as MV Ampere and Ellen have Li-ion batteries ranging from 1000 kWh to 4300 kWh. On the other hand, Movitz is a smaller ferry and uses 120 kWh nickel-metal hydride (NiMH) batteries. Conversely, Aditya has a Li-ion battery of only 50 kWh, indicating a smaller capacity. These battery characteristics provide important information about how far each ferry can travel and how many passengers or vehicles it can carry.  
\begin{table}
\begin{tabular}{p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt}} \hline \hline
**Name** & **Country** & \
\begin{tabular}{} \end{tabular} &
\begin{tabular}{} \end{tabular} & **Battery** \\