Examination of Departure Battery Capacity by Battery Specific Energy and Power Analysis

To reduce CO2 emissions from ships, efforts are being made to electrify and hybrid ship propulsion systems. By newly mounting a battery as a power source, zero emission at a port of entry or departure is realized by the energy of the battery, and zero emission in a ship during cargo handling is realized by the energy of the battery. However, the kinetic energy of the hull has not yet been effectively utilized by regenerating electric power. we obtained 12% regeneration energy amount at the time of entry and 5.66% regeneration amount at the time of departure when the opportunity of energy regeneration is not expected by the experimental analysis. This paper clarifies what kind of operation should be carried out to charge batteries and enter the port in order to cover all necessary energy at the time of departure with regenerative energy. The energy quantity required for the departure and the maximum power output of the main engine at the departure were obtained, and the relation between the power density required for the battery and the energy density was clarified. This paper concretely mentions the feasibility and necessary number of the existing mass-produced EV battery box.