Adding 2nd battery to 2021 AR210

[Shadowrider]

To start, I stupid when it comes to electrical anything. Light switch, ceiling fan, okay I can do that but not much more. I want to add a second battery to run stereo and such, but more importantly just in case the primary dies. Watched dozens of videos on YouTube but most are more involved than I can comprehend with filled with gobbledygook terminology and people telling stories about how they use the boat and tons of add on electronics. I simply need to add second battery that will charge just like 1st one and be available to crank up in the event it's needed. It seems from everything I've read and seen that blue seas systems add a battery mini (60 amps) switch and ACR will meet my needs. Any thoughts and (keepitsimplestupid KISSPRINCILPLE) would be really appreciated. Please dumb it down for me. Thanks in advance everyone . Almost forgot to ask what battery to get, same as the OEM cranking battery, or something different?

 

[Yammi]

I added the blue seas systems add a battery mini last year to a boat that had a 90 HP outboard and a single battery. It really is piece of mind knowing that it will charge both batteries without having to do anything, its automatic...and that running electronics will not be an issue when it comes to starting because it isolates your starter battery and our house battery. Yamaha is offering a similar system with the automatic charging relay (ACR) system - FSH 210.

For the blue seas system, I ended up making my own wiring, which was simple....believe I used 4 AWG. I followed the wiring directions and mounted the switch in a convenient location so I could switch it on and off without hassle. I think I also used 60 amp fuses on either side of the ACR.

wiring diagram

 

[HangOutdoors]

@Shadowrider I did the same thing this last spring to my 2020 AR210. I also purchased a nice North Star AGM Battery for my second battery. Also note I have additional batteries for the trolling motor but they are not show here. I used buss bars and fuse blocks as well as breakers. You don't have to but it cleans it up very nicely. The thought is down the road you may be adding additional things like Tabs, Chart Plotter, Additional LIghting, Amp, Speakers, etc. Fume Detector, a high water alarm, CO Detectors and/or an additional bilge pump, additional USB charging ports in different areas of the boat.

Anyhow here is my build. And my parts list. Note I did run another fuse block up under the helm. Figured if I am doing the battery now may as well do it all right. It is not that hard. I can walk you through everything if you like.

Pictures

https://jetboaters.net/threads/wiring-and-battery-addition.32539/post-527918

Wiring and Battery Addition | JetBoaters.net - The World's Largest Jet Boat Forum!

Here is my shopping list. Also I made my own positive and negative wires.

https://jetboaters.net/threads/wiring-and-battery-addition.32539/post-527932

 

[Shadowrider]

Wow, thanks so much for all the great info. I'll likely be doing the add on in the next 2 weeks and will reach out if I need any additional help. Once again, thanks and happy holidays to all.