Decent boat batteries don’t come cheap and then of course there is the difficulty in fitting them into what is more often than not a tight and awkward spot.  But if you take care of them following our tips below, they can last for 5 to 7 years (sometimes more sometimes less) 

  1. Monitor the battery state.  Just as you would keep an eye on how much fuel you have in your tank, the same line of thinking should be applied to your battery state of charge – if you want to avoid being stranded with a flat battery that is!  Accurate battery monitoring is essential to prolonging the life of your battery.  Discharging batteries below 50% will dramatically shorten your battery’s life, while regularly flattening the battery can destroy it, resulting in battery failure in a few months.  So, in a nutshell to preserve your batteries life you would want to make sure it’s charged before the voltage falls to 12.2V in a 12V battery.  The easiest way to monitor this accurately and thus stay on top of things will be through the use of a battery monitoring system. 
  2. For Deep Cycle batteries (batteries that are used to power electrical equipment when the motor isn’t running) calculate your daily power use Ultimately this comes down to size, battery size that is.  If your boat battery isn’t big enough you will be taking out too much charge each day.  So, choosing the right battery size for your needs is key.  Roughly speaking your batteries should be sized 3 times more than your boats daily electrical consumption, calculated as: Daily power consumption = Current in Amps of each electrical device x length of time (hours) used in a 24 hour period measured in amphours. The amphours rating will be on the deep cycle battery. 
  3. Reduce your power requirements.  This is by far the simplest way to prolong your boat battery life and are good practices to employ at home and in the car for the same reasons, – it takes little effort and will save you money in the long run by reducing your energy/electricity consumption.  But I digress, back to the boat, here are some of our best suggestions (we’d love to know if you have ones that have worked particularly well for you), frozen bottles of water in the fridge, ensure the fridge is adequately insulated, don’t leave lights on when not needed and if you haven’t already change to LED bulbs. 
  4. Add a solar panel.  If your boat sits idle a lot, a dead battery can be an all too common occurrence.  This frustration can be easily avoided by installing a solar panel which can keep your battery topped up.  That said not all solar panels are created equal so you should choose according to your needs and if in doubt seek advice.  An added bonus with the solar panel is, it’s environmentally friendly, so you’re winning on two counts with this one. 

Let’s face it marine conditions are pretty tough on your batteries, but by making sure you get the right batteries for the job and with a bit of basic battery maintenance and monitoring you’ll head off early battery failure.    

We hope this guide has helped. Tight lines and happy boating. 

Need a boat battery?  Pop in and see us or visit us online for a wide range of trusted brands backed by a warranty and expert advice.