Boat House Battery solution required?

Question

Hi, I have a twin engined 32ft cruiser which I stay overnight on regularly. Problem is the House Battery does not seem to cut it. By morning it's already pretty flat just running a fridge and freshwater supply and the occasional use of the Inverter.

The house battery is an N150 Truck and Tractor battery. I don't have a genset and don't want to install one due to weight, mtce and ongoing cost.

I was told that the current battery is not suitable as it should be a deep cycle battery with a special regulator on the alternator for charging.

So my choices are to get to new deep cycle batteries and a new charger, but will the deep cycle batteries be suitable for cranking the second engine which is connected to the house supply or will I need to consider rewiring to the main starting battery?

Wind turbine and solar charging are not suitable for this vessel.

Open to any suggestions.

Thanks Steve

Answer 1

You will always have a problem with power unless you put enough battery to carry the load all night> Add up all the watts your using> For starter> 4- 6 volt will get you going> But charging them up with out a 100 amp charge you will not be able to fully charge then off your main engine with a 35 or 50 amp charger unless you run it all day> Have cruised for 15 yrs> Battery's power & charging is the biggest problem> I have>a 2500 watt inverator with a 100 amps charger> For 9-6 volts runs all 12V + freezer & fridge TVs> with a 8 kw generator> For charging water maker 2 A/C micro & stove> Home away from home> 48' sportfish>

Answer 2

Deep cycle batteries are designed to discharge and charge slowly for many cycles.  Starter batteries are designed to put out a lot of amperage for  a short while, then recharge quickly. Using them the wrong way will shorten their life span.

The best solution is a starter for the engine, one or more deep cycle for the house, and an isolator between so they can all charge at the same time, yet not drain each other.

Answer 3

We had a smiler Problem, I solved it buy adding one more  Deep Cycle Battery, I hook two Deep cycle Batteriess together in series for the House system on the number one Switch and the one for Starter on number two.  If Need be you can switch to both and have amperage from all three to start your engine,s, Yes Deep Cycle batteries,s get Pricey but when your out in the Middle of no were with dead Batteries,s How much would you give for a Little extra Juice.

My Alternator handle,s them just fine, Charging on Switch One or Two but not Both.

I am assuming you Have a Batterie Switch, It Also is Kind of Pricey but a very good investment for any boat.

Answer 4

You need to add a deep cycle batt for the house bank. Your alternator(s) should be fine. Get a 1,2,both,off  battery switch if you don't already have one. Save the N150 for starting. The switch allows you to parallel if needed. The deep cycle can also be used for starting but won't likely be needed when your N150 is now used for starting only.

If you can...look at all your loads...in terms of Amp Hours useage...this will tell you how big a Battery you need in terms of reserve capacity. You might consider 2  6V combined to get huge reserve capacity in a smaller footprint.

Alternator being fine is a relative term...sorry...if you want to run your engines less...get a bigger alternator on at least one of your engines....like a Balmar 100 or 105

Good luck

Answer 5

you need what is called a deep cycle batteries which all boats use and if it is correct should fix most of your problems. They are designed to be run for a long time and be able to start the engine after. They are also dearer to buy but is also why many people try to fix cheaply and not fit correct batteries

Answer 6

Once again I agree with Dave M ... compute your actual amp hour needs and install deep cycle batteries to provide that amount with about 25% overhead reserve. Split your system so that you have a house bank and engine bank. You can install a combiner between the banks to allow you to use all your batteries if necessary. I have 2 separate systems with 2 group 27 dual purpose batteries on my engine bank and a D4 and 2 group 27 deep cycle batteries on the house bank. Each bank is on its' own switch with a combiner between the 2 banks,  100 amp alternator and solar panels.  I have never run out of electrons.