Care and Maintenance of Lead Acid Marine Batteries on Ships
Lead-Acid Batteries on ships provide an important function.
In the event of a ‘black out’, or loss of generator power, they allow the ships important systems to continue to operate, until backup generators ‘kick in’, or repair can take place.
Important systems include communications, such as radio, sat comms & radar. They also crucially include the ships steering gear system.
Proper and regular care and maintenance of the ships batteries will ensure maximum reliability & safety.
The electrolyte contained inside the batteries is sulphuric acid, therefore contact with skin, will result in skin burns.
Therefore protective (PPE) clothing is needed before maintenance work can commence.
Protective clothing items include goggles, rubber gloves and rubber aprons.
Consult your marine employers health and safety rules, for the required items.
When the batteries are being charged by the ships electrical system, potentially explosive gases are produced by the batteries.
Therefore the following precautions need to be taken, to ensure safety:-
- No Smoking or naked flames.
- Switch on the battery rooms ventilation fan. The fan should be capable of extracting the volume of the rooms air, once a minute.
- Do not use metal jugs for topping up the electrolyte (with distilled water). This is because the metal conducts electricity, and therefore there is a risk of creating a spark.
- Keep tools and loose wires off the top of the batteries. This is because they may cause a short circuit, and spark, if they short between the battery terminals.
- Examine the battery terminals to ensure that they are in sound condition, and tight. This is to prevent potential sparks from a poor connection between the terminal and battery post etc.
Dilute sulphuric acid should be washed off skin as soon as possible.
If the acid comes into contact with eyes it requires immediate attention. It should be washed out immediately with water or a dilute saline solution. Commercial saline eye wash products should be available in the battery room first aid kit.
If for any reason there was no saline eye solution available (should be), then a saline solution can be made using one level teaspoon of household table salt, to half a pint of water.
A quick and rather ‘alternative’ emergency method is to immerse the victims head in water, while they open and close the eye under water.
Marine batteries should be kept clean.
The following tasks must be carried out on a regular basis (see your company’s maintenance schedule):-
- The top of the battery cells must be kept in clean condition. Remember to wear appropriate PPE clothing, while carrying out task.
- Coat all battery terminals and links with a coating of petroleum jelly (not grease). If you have no petroleum jelly available, then ‘vaseline’ is basically the same stuff, with a nice smell. However this is only a suggestion for a temporary emergency situation. My advice is to always use the correct stuff.
- Ensure that the ‘Gas vents’ in the battery cell plugs are kept free from blockages. The vents are small holes in the plugs, that allow the gases to ‘escape’.
- Remove the ‘cell plugs’ and top up each cell (if needed), so that the level is a little above the top of the ‘plates’ (the grey metal things inside the cell holes) Pure distilled water is what you need to top up the cells with.
- Test the ‘specific gravity’ of the electrolyte solution, using a hydrometer. This will give you an indication of the lead-acid batteries state of charge. A fully charged marine battery will have a specific gravity of 1.280 at a room temperature of 15.6 degrees Centigrade (60 degrees Fahrenheit). Note: You should use temperature compensation charts for your specific environment, as it affects the readings.
- Voltage checks, using a voltmeter can also be carried out.
If you find that one or all of your marine batteries have gone ‘flat’ we can examine the situation in order to solve the cause.
If the marine installation has multiple batteries and its own battery room, then are all not charging?
If none are charging, then the fault is unlikely to be the batteries.
More info coming later.