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The Main Dock => TSBB General Talk => Topic started by: Wolverine on Dec 18, 2025, 05:31 PM

Title: Question for Those Smarter than Me
Post by: Wolverine on Dec 18, 2025, 05:31 PM
Okay, so I guess this is for everyone. ::) I have 1 battery on the boat connected to a 4 way switch. Off, bat 1, bat 2, both.
A 50 watt solar panel is mounted on the cabin top leading to a charge controller and then to the battery. I just purchased a second battery and would like to wire it to the controller too. If I connect the batteries in parallel, will they both get an equal charge from the controller?
Title: Re: Question for Those Smarter than Me
Post by: tjspiel on Dec 18, 2025, 05:44 PM
I can't speak for every set up but I know for the LifePo4 batteries I have, they recommend that you fully charge the batteries individually before connecting them in parallel and that you should connect them with bus bars.

But yes, you should get equal charge that way. And if they are LifePo4 batteries, I'm sure that they'd also recommend that you get the same brand and size so that the battery management systems will behave the same way.
Title: Re: Question for Those Smarter than Me
Post by: Wolverine on Dec 18, 2025, 07:06 PM
Yes, they are the same brand/size LifePo4. 100ah each.