There are a number of important factors to consider when buying a leisure or marine battery including;
Size - will the new battery need to fit in a locker or particular space
Voltage - usually 12 volt but sometimes its 2 x 6v batteries or more
Capacity - this is the amp hour rating or AH for short. What does this rating mean? In simple terms a 100 ah battery attached to say a light which is consuming 2 amps will run for 50 hours. 2 x 50=100ah.
In practice batteries deteriorate with age, suffer a loss of capacity with cold temperatures and its bad practice to discharge them more than 50%. You may well feel that your old battery had insufficient capacity aand look for one with more amp hours.
Battery life - Battery life is reduced dramatically by deep discharging - always source and fit a battery that has a suitable amp hour AH capacity.
Battery location - if your battery is located in an external compartment thet most battery types are suited, however, if your battery is located internally to the boat or caravan - motorhome - its best to use a sealed, agm or gel type battery. Note that the sealed maintenance free type will still require venting - a small tube should be connected to the central gassing port and piped outside. All vehicles should be fitted with these when new.
Battery charging - all of our batteries require correct charging in order to gain full capacity and provide a useful long life. Multistage chargers and solar panels will provide longer running times and a happy battery.
Always ensure the venting pipe is correctly fitted if required
Avoid naked lights or sparks/ flames when working around batteries
Remove the negative terminal first - reconnect last
Disconnect the charger before working on the battery system
Ensure your battery is securely fixed in position