Battery set up for Pontoon

[biglurr54]

I have a 16ft pontoon that I restored. It is docked at the lake all season. I do not have power at the dock and no reasonable way to get power to the dock. THe pontoon is powered by a 1989 30hp Evinrude. I typically brought along a bluetooth speaker for tunes while floating but this year I installed a bluetooth receiver and a speakers in the pontoon. The wiring has a 10amp fuse so It not a massive amp. Currently I have a cheap walmart lawn mower battery (4 years old now) that i use to start the motor. It has worked great the last 4 years and for $20 you cant go wrong. I am worried about running the speakers off the battery while floating with the engine off.

I have a couple ideas:
1: for $100, I can buy a deep cycle marine battery and just run that one battery and hope that the deep cycle wont get killed by the radio and will stay charged up with the motor running. (We usually arent floating longer than 3 hrs anyways)

2: Add an Isolator switch (80amp Stinger Isolator $16.50) and a small 12v 24ah deep cycle battery. This will isolate the deep cycle battery with the switch off, but allow the stereo to play off the deep cycle and preserve the starting battery, and then reconnect the batteries when the key is turned on.

3: Bring out the bluetooth speakers again. (I would rather use the onboard radio then the bluetooth speaker)

I can also add a solar charger to keep the batteries up while docked. There is no other electrical load on the pontoon.

 

[ThomW]

My personal preference is to have two batteries and a battery switch. I have a size 29 deep cycle battery and a 24 cranking battery. They are hooked up to a 1/2/both/off perko battery switch. When I am cruising along, I keep switch on both, so both batteries are charging. Then, if a am beached or floating, I will switch it to the deep cycle battery to play the radio. When its time to go, I switch it back to both and start her up. If that doesn't work, switch to the cranking battery and it should be fully charged. Prevents you from ever having to worry about being stranded with no way to start the motor. Just make sure the motor is off any time you go to switch the battery switch from battery to battery.

 

[biglurr54]

My personal preference is to have two batteries and a battery switch. I have a size 29 deep cycle battery and a 24 cranking battery. They are hooked up to a 1/2/both/off perko battery switch. When I am cruising along, I keep switch on both, so both batteries are charging. Then, if a am beached or floating, I will switch it to the deep cycle battery to play the radio. When its time to go, I switch it back to both and start her up. If that doesn't work, switch to the cranking battery and it should be fully charged. Prevents you from ever having to worry about being stranded with no way to start the motor. Just make sure the motor is off any time you go to switch the battery switch from battery to battery.

Thats how I have my bowrider set up. Its a pain to keep switching the switch for the batteries. Half the time I forget. The Battery Isolator does that automatically. It sense the if the ignition key is on or off. (Or you could use a switch on the helm with 12vs.) If the key is off the isolator separates the batteries. If the ignition is on, it combines the batteries. Plus its cheaper than the Perko switch.


I think option 2 with a 50w solar panel attached to the deep cycle battery would be a good set up. the 50w panel puts out 2.90 amps at 18.3v (optimal). Say I get an average of 2 amps (losses due to charger and less then optimal positioning) for 7 hours a day. Thats 14ah replaced. I doubt i use more than 2 ah per hour while floating with the tiny system.

 

[biglurr54]

Well I set up a 50 solar panel and charger to a 18ah wheelchair battery. This set up is completely separate from the starting battery. I have blasted the stereo for hours at the dock with no issue. The charger always shows the battery is holding at 13.7v. I think i may upgrade the charger to a 2 battery charger and charge both batteries with the solar panel.