Adding a Third Battery

[JLR]

I have a 2013 Grady Freedom 285. It has twin Yamaha F300's. I also have a battery charger used when I plug in to dockside electric. However, I only have two batteries. Both are dual purpose and I have never really had an issue with not having enough juice for all of my electronics. Does it seem odd that a boat this size with plenty of electronics only came with two batteries and two battery switches. Has anyone added a third battery to boost its house battery capacity and if so, what are the considerations in doing so? Thanks.

 

[seasick]

If everything works fine and you never had an issue, why change it?
Sure you could add a separate house battery but to be done correctly, electrical changes would have to be made assuming that the new house battery would be a deep cycle type. You should not parallel batteries of different types, makes or ages.
You would have to decide how you want to rewire the house feeds and what option you want to implement of charging, both the motor charging and the shore power system.
You know what they say." If it ain't broke, don't fix it"

 

[DennisG01]

When you say "plenty" of electronics, what are you talking about? How long do you use your electronics with the engines off? If you're just talking about standard stuff, then that's not really all that much. Being a simple bowrider you're not going to have tons of 12V items drawing power like a cruiser would. It's not like you're staying overnight on the boat and using 12V items with the engines off all night. I'd say stick with what you have - with simple/basic systems, there's really no need to change things up.

 

[SkunkBoat]

idk your model setup.
Usually, the starboard bank is the House and starting battery
On the larger boats, grady often used two parallel batteries(same type) on the starboard side.

Assuming you have space...
In the simplest configuration you would just add a battery in parallel next to your stbd battery and nothing else would change. To be sure they are same battery, you could put the existing port battery there and get a new port battery.

Your charger would connect cross corner on the bank of two.

If you are a day boater at the sand bar, the only reason you would need more battery is if you have a high watt stereo with 17 speakers and you want everyone to listen to Country Hits all day.

 

[Fishtales]

A GW that size had 4 batteries in the past. I'm guessing all the creature comforts they install took up space. If you can fit them in, add them if you want. There will be wiring changes but likely can be done. Only time, money or a little/lot of both.

 

[JLR]

Thanks all. I do not operate the boat at all with the engines off when not plugged in to power. Sounds like I'll stick with what I have for now.

 

[DennisG01]

Thanks all. I do not operate the boat at all with the engines off when not plugged in to power. Sounds like I'll stick with what I have for now.

Then this is all pretty much a non-issue. In this case two batteries is plenty. Even a few hours of listening to the radio with the engines off will be fine with just two batteries.

 

[dogdoc]

Cannot understand why a manufacturer would produce a boat like yours without a dedicated house bank. If it was my boat I would add one, but that is me.

 

[DennisG01]

Cannot understand why a manufacturer would produce a boat like yours without a dedicated house bank. If it was my boat I would add one, but that is me.

It's a bowrider, though. There is no "house" to speak of. It's basically the same (from this standpoint) as an 18' bowrider. Granted, it's a whole lot nicer - a LOT nicer. But the use of batteries is the same.

 

[dogdoc]

Went to the GW site and looked at what comes with new model 285. Only 2 batts. A lot of pumps and lights and options for more power grabs, power sun shade, bow thruster, etc.... That's not even getting started with the electronics. Sorry 2 batts seems light to me.

 

[DennisG01]

The bow thruster is a high draw item (does it run off the two engine batteries or is there a separate bank when that option is selected? I honestly don't know) - but that item would only be used when the engine is running so it's sort of a moot point.

LED lights draw an extremely small amount of current - a couple hours of use won't cause any issue. I've done longer times with higher draw lights with no issues. Pumps draw more - but with a bowrider style boat it's not like fishing is the main thing - you're not out 10 miles off shore drifting without the engine running for hours on end with this style boat. Electronics on this style boat would be used primarily with the engine running.

Same thing with the sunshade - relatively small draw for a very short time (and "could" be done with the engines running, although by no means necessary).

For 99% of the people using this style boat, the redundancy of 2 batteries are just fine... for the INTENDED purpose (different than a walk around or possibly even a CC). And, for the OP here, it does seem this has been just fine for him and will continue to be so.

Practically speaking, 2 are just fine. But... it's all good - that's why we have options!

 

[SkunkBoat]

those bow riders tend to have 1500W amps and 17 speakers....

 

[Fixit]

I have two starting and three deep-cycle group 31 batteries in my 270 islander. I do some overnighting and need the fridge to run for a few days some times. its augmented by 100W of solar and I use solid-state argofet charge isolators (fancy diode like devices that dont have the associated voltage drop across them). I have the typical loads- fridge, three screens, radar, power steering, etc. Like the bow riders I too have twin amps 1400W/2250W for the 8 speakers and 1 sub. I use bluesea 5511e batterie switches. one turns on both engines the other switches the house loads on. both can be combined to join starting or add the house bank to starting batteries.


IMO your starting batteries should do one thing. supply power to your starter and crank the engine.
the house should be running everything else and could be totally dead, but you should be able to start your engines and drive home.

your engines should be supplying all the needed power while under way, plus charge all the batteries. it doesn't sound like you have much for electrical demands but I would still consider a dedicated house bank. its the redundancy of never having a dead starting battery

 

[seasick]

I have two starting and three deep-cycle group 31 batteries in my 270 islander. I do some overnighting and need the fridge to run for a few days some times. its augmented by 100W of solar and I use solid-state argofet charge isolators (fancy diode like devices that dont have the associated voltage drop across them). I have the typical loads- fridge, three screens, radar, power steering, etc. Like the bow riders I too have twin amps 1400W/2250W for the 8 speakers and 1 sub. I use bluesea 5511e batterie switches. one turns on both engines the other switches the house loads on. both can be combined to join starting or add the house bank to starting batteries.


IMO your starting batteries should do one thing. supply power to your starter and crank the engine.
the house should be running everything else and could be totally dead, but you should be able to start your engines and drive home.

your engines should be supplying all the needed power while under way, plus charge all the batteries. it doesn't sound like you have much for electrical demands but I would still consider a dedicated house bank. its the redundancy of never having a dead starting battery

Very interesting install. How are the house batteries wired to the loads. Are all three in parallel or are specific loads connected to individual batteries? How did you wire battery switches? Does non cranking power for the engines come from the start batteries or the house pair.

 

[DennisG01]

those bow riders tend to have 1500W amps and 17 speakers....

Good point! And for some reason, some people with these systems often only seem to have one volume setting

For the OP, though, he stated his engines are always running when he's away from the dock. The OP's boat is 11 years old, so probably not the same as newer boat systems, either.

 

[Fixit]

How are the house batteries wired to the loads. Are all three in parallel or are specific loads connected to individual batteries?

all three house batteries are in parallel with each other I have a three buss bars. a switched (downriggers add-ons etc), unswitched (solar, high water bilge pump/alarm) and the heavy wires one (stereo/amps, windlass, etc)

How did you wire battery switches?

see pict... but the switch is a dual pole single throw (two separate circuits energized at same time, but you can emergency combine the two start batteries. the house switch just turns on the one circuit. the emergency combine sends power to the port cranking battery

Does non cranking power for the engines come from the start batteries or the house pair. - Everything engine related is from the cracking batteries

and a picture of the 2250W subwoofer that only knows one volume

 

[seasick]

Thanks for the info.

 

[DennisG01]

and a picture of the 2250W subwoofer that only knows one volume