Annex 1 - Rechargable Accumulator Batteries
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Statutory Documents - IMO Publications and Documents - Circulars - Radiocommunication and Search and Rescue - COMSAR/Circ.16 - Guidelines on the Configuration of the Reserve Source or Sources of Energy Used to Supply Radio Installations on GMDSS Ships - (4 March 1998) - Annex 1 - Rechargable Accumulator Batteries

Annex 1 - Rechargable Accumulator Batteries


Rechargeable accumulator batteries as installed should meet the general requirements set out in regulation IV/13 of SOLAS 1974, as amended, and in resolution A.694(17), as applicable and should also comply with the following requirements.


2.1 Any type or construction of batteries (e.g. lead acid, alkaline, maintenance free, traction, semi-traction, etc.) may be used as reserve source or sources of energy, taking into consideration the environmental conditions of the location where they are installed.

2.2 The capacity of the battery should be sufficient for the load determined in accordance with the annex, paragraph 2.4.

For guidance, the nominal battery capacity to comply with the minimum capacity requirements at all times is 1.4 times the load determined in paragraph 2.4 multiplied by the intended period of operation (1 hour or 6 hours in accordance with SOLAS IV/13.2).

2.3 The battery should maintain its rated capacity when inclined at any angle up to 22 in any orientation.


3.1 An instruction manual which contains all necessary specifications of the batteries should be available on board. The information should include at least:

  • .1 capacity and temperature range within which the stated capacity is maintained for the specified operation period i.e. 1 hour or 6 hours;

  • .2 charging voltage and current limits in order to keep batteries fully charged while preventing overcharging;

  • .3 actual specific gravity of the electrolyte and/or cell voltages or the voltage of the fully charged battery;

  • .4 guidelines on how to carry out a controlled discharge test;

  • .5 methods of determining the condition of charge of the battery, e.g. check of specific gravity of electrolyte (acid density) or check of battery cell voltages/battery voltages byusing an accurate measuring instrument in accordance with the battery manufacturer's specifications;

  • .6 requirement for ventilation; and

  • .7 requirements for maintenance.


4.1 The batteries should be properly marked with type or construction, rated capacity (capacity for 1 hour discharge C1 and capacity for 5 hours discharge C5), and installation date. The marking must be visible after the batteries have been installed and during their lifetime.

4.2 A label warning of explosion danger should be displayed near the installed batteries.


5.1 When defining the minimum required battery capacity, consideration should be given to the expected extreme temperatures for the location of the battery and reduction of its capacity during its lifetime in addition to the loads which are to be connected to it.

5.2 The temperature range of the battery should be wider than the expected temperature range of the location where the battery is to be installed.

5.3 Equipment requiring lower voltage than the total voltage of the battery bank should not be connected to a part of the battery bank.

5.4 The batteries should be installed in an elevated position in the ship and as close to the radio equipment as possible.

5.5 An outdoor located battery case should be avoided due to considerable temperature variations.

5.6 Batteries of different types, different cell constructions, different capacities or different manufacturers should not be mixed in a battery bank.

5.7 Batteries of different types and different cell construction should not be installed in the same location if they can affect each other.

5.8 Sufficient ventilation for the battery should be provided, as required by the battery manufacturer.

5.9 Electrical installations including battery chargers, located in the battery room should be intrinsically safe.

5.10 Sufficient space between batteries and battery banks should be provided for carrying out inspections and maintenance. The batteries should be well braced to remain firmly fixed under all sea conditions.

5.11 The cabling from the batteries should be protected against earth- and short-circuits and be appropriately fused and installed according to recognized international standardsfootnote. Battery cables should have sufficient dimensions to prevent voltage reduction at peak current consumption.

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