When using an accumulator battery as the Emergency source of electrical power, it is important to ensure that the battery can carry the emergency electrical load without needing to be recharged.
During the discharge period, the voltage of the battery should remain within 12% above or below its nominal voltage to ensure it continues to function properly. This is as per SOLAS Chapter II, Regulation 42.3.2 which also states that the power from the emergency battery should automatically connect to the emergency switchboard in the event of failure of the main source of electrical power; and immediately supply to the connected services.
No accumulator battery fittedbyh this regulation shall be installed in the same space as the emergency switchboard. An indicator shall be mounted in a suitable place on the main switchboard or in the machinery control room to indicate when the batteries constitute either the emergency source of electrical power or the transitional source of emergency electrical power.
Accumulator batteries shall be so designed and arranged as to ensure that they will function at full rated power when the ship is upright and when inclined at any angle of list up to 22.5 ° or when inclined up to 10° either in the Core or act direction, or is in any combination of angles within those limits.
As per the regulations outlined in SOLAS Chapter 4 Part-C Regulation 13, the batteries used for GMDSS (Global Maritime Distress and Safety System) must be able to power it for at least 1 hour if GMDSS has the power from emergency generators, or for 6 hours if GMDSS doesn’t have the power from emergency generators.These batteries must bee recharged to the required minimum capacity in less than 10 hours.
Furthermore, it is important to regularly check the capacity of the batteries at intervals of less than 12 months to ensure they remain in good working condition and can be relied upon during an emergency situation.