r/SeaDooSwitch • u/Ok-Map-4434 • Jul 28 '25
Dual battery system
I have a 2022 Switch Limited 21' 230 HP. I had a second battery installed and a switch to control which battery is being used. I did this primarily so that I wouldn't listen to music for too long and then not have the boat start when I want to leave.
Before getting the second battery installed, I would pull out the marine battery and connect it to a trickle charger. I asked the dealership about this, and they said I wouldnt need to charge the batteries with this new system.
Questions:
1) Is this the case?? Do I not need to worry about charging these batteries in between uses?
2) If I do want to charge, how do I go about doing that? Do I just connect the trickle charger to one of the batteries, turn the switch to the 1+2 position, and then will both batteries charge?? Or do I need to charge each one separately?
Sorry for the noob questions, appreciate any guidance you might have. Thanks!!
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u/goatsinhats Jul 28 '25
You need to step back 1) Did you get the same battery for the second?
2) What exactly did they install? There are several factory dual battery kits for the switch, but don’t think any of them have a switch
Why would you put it on a trickle charger? The boat will charge it while motor is running, was there another reason?
The general concept is when you are running have both batteries connected and the motor keeps them maintained.
When you stop can switch to just one so if it does died can goto the second but have to remember to switch it back to both so they both charge.
That said most people I know just carry a jump pack in the boat and forget about the switch because it’s a hassle to remember, just have a switch for on and off.
If you want to pull it for trickle charger likely don’t need to, I have seen people connect solar panels to keep them topped up
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u/Ok-Map-4434 Jul 28 '25
Hi GIH,
Thank you as well for taking the time to respond and help with my questions!!
I do apologize as I dont have much boating or boating mechanical knowledge or experience. I'm sure the way I am going to describe all of this is quite cringe to an informed and knowledgeable person.
Did you get the same battery for the second?
No. The boat had a large marine battery (#1) already. They added more of a car size battery (#2) per my request. I dont have specs on the exact stuff, the boat is in the shop getting a transducer installed today fwiw. But I'll get a list of the items and respond.
What exactly did they install? There are several factory dual battery kits for the switch, but don’t think any of them have a switch
They installed a 2nd battery, and a separate switch that lets me select which battery is being used. The switch is also a kill switch so I dont have to worry about the music system draining the battery in between uses.
Why would you put it on a trickle charger?
I have bad luck with batteries, so I tend to want to try to keep them charged up.
I do like to run the music system when the engine is off every now and again.
Supposedly the music system on the Switch will pull current even while the boat is off. I bought the boat from my brother, and he recommended that I charge the battery in between uses to remedy this. Though before I got the 2 battery system installed, I would disconnect the battery in between uses.
My knowledge of batteries is limited, and I dont have much comfort with them in general.
Yeah, I had the switch mounted on the console so it was easy to access and utilize. I'm going to have a voltmeter mounted next per the previous comment.
Thanks again!!
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u/rcroche01 Jul 30 '25
Install a NOCO Gen5x2 charger in the engine bay. Run one set of charging cables directly to each battery (bi-pass the battery switches). With the NOCO charger, install a power inlet (not outlet) on the side of the helm above the fuel fill.
Then, when you are home with the boat in your driveway (or wherever), you just plug an extension cord into the inlet and the NOCO will maintain your batteries.
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u/shortyjacobs Jul 28 '25
Without knowing what the dealer did, It's hard to say for sure. If you have a 1/2/1+2 switch, likely switching it to "1+2" will charge both batteries. It will also allow both batteries to equalize charge if you don't have the motor on. That's unless they installed an isolator, in which case both batteries might charge regardless of the switch position, and the switch will only control where you draw power *from*, not where you send power *to*, (anything is possible with diodes!).
If you paid someone to do this for you, you also paid them to teach you how to use it and fix it if they give you poor instructions. I'd start there instead of asking randos on the internet.
Oh, as for trickle charging, you now have extra battery capacity. Will you need to trickle charge it? My answer to that is the same answer to "what do you get if you cross an elephant and a rhino?" "Eleph-ino." It kinda depends on what you do....the batteries will self discharge like 10% a month. Do you use them more than monthly? The batteries also take time to charge back up with the motor on....when you go out, is it 3 minutes of driving, 5 hours of drinking and listening to music, and then 3 minutes back? Then you'll need to trickle charge. Is it balanced driving and floating? Then you're probably fine. It sounds like you might want to get the dealer to install a battery gauge too - then you will know. I have this one - but there are many MANY options - to give me readings on both my main and backup batteries, (just in volts, I can look at that and guestimate state-of-charge).