See full version: Boat Battery Basics
Until the recent advent of electronic chargers we had big problems with ferroresonant chargers overcharging and damaging batteries. Now, to the best of my knowledge, all electronic chargers provide the basic 3 stage charging with electronic sensing that prevents overcharging. Therefore, if you have an old charger and are having premature battery failure problems, you'd best replace the unit. Symptoms of overcharging are hot batteries and unusual fluid loss.
Charging is a complicated issue that I'm not going to get into here beyond saying that battery charging becomes a problem when engines aren't operated long enough to complete a full charge, such as infrequent use and frequent starting and stopping. This happens as a result of short runs, as in fishing. For boats that are always on shore power systems when not running, this isn't a problem. Outboard boat owners most often suffer from battery failure due to incomplete charging. Achieving a complete charge will take several hours at least, so when you're operating for shorter periods, it is likely batteries aren't being fully charged.
Failure within 24 months from the date placed in service yields FREE REPLACEMENT, not including freight charges from the factory to the applicable destination. After the first 24 months of service, defective batteries will be adjusted for a period of up to 60 months prorated from the date first in service at prices in effect at time of adjustment [links]
A cranking battery repeatedly used for deep cycling can degrade in a matter of weeks, and vice versa, so choose the right one. more
Marine battery maintenance means more than regular charging. Neglecting other forms of maintenance can also lead to deterioration. here
Purchasing a second-hand battery is generally inadvisable. You don’t know its history and it’s probably not covered by the manufacturer’s warranty.
External components should also be inspected. Check that the lead posts don’t show signs of coming off (they can be weekend if a terminal was forcefully connected). A gentle dose of grease, lanolin or Vaseline can stave off corrosion on exposed metal terminals. Once a year, clean out the battery box, check for signs of leaks and corrosion, check the vent is clear, and inspect the tie-downs. [links]
Deep-Cycle – a deep cycle battery offers a lower and more steady rate of energy than the cranking battery. This means that you can run all of your electrical equipment without the risk of having to charge your battery on the water.
This simple action will add life to your battery and slow down its rate of self-discharge. Make sure no cracks or malformations appear in the casing. If so, it could mean a problem with the voltage and you’ll want to have it checked out. If you’re getting ready to store for the winter, make sure you store all marine batteries fully charged and in a climate controlled environment. Chargers may just be accessories, but using a top quality marine battery charger is a great product to have, since you never want to store a battery that’s discharged.
Wet-Cell Battery – the most common and typically the most affordable. They contain many cells with an electrolyte liquid most of us call battery acid. more
Furthermore, what is the minimum voltage for a deep cycle battery? Deep Cycle Batteries in a cycling application require a recharging voltage of 2.43 to 2.45 volts per cell. This is 14.6/14.7 volts for a 12 volt nominal installation and 29.2/29.4 volts in a 24 volt site.
Is 12.3 volts a good battery?
In respect to this, how many volts should a marine battery have? more