question

pcking avatar image
pcking asked

What is the best solution to have my boat engine charge both the starting and trolling motor batteries?

Looking for a safe option to charge my new BattleBorn 100 Ah 12V LiFePO4 Deep Cycle Battery...

I have a small boat with a 15A alternator and a Marine deep cycle starting battery.

Here are the motor specs, in case you need them.

https://www.evinrude.com/en-US/e-tec/e-tec-full-specs.html#tab=11

https://www.evinrude.com/content/dam/evinrude/Global/MY2020/Documents/outboard-specs/ETEC-30-HP-Outboard.pdf

Alternator Output

56 Amps Total / 15 Amps Net Dedicated


I have been looking at the Orion TR-SMART 12/12 family and wondering if I can use the 18A unit despite my alternator output being just 15A... or is the 9A version a safer choice?


Obviously I want to get as much charge as I can, but also want to be sure both the alternator (Stator) and the LiFePO4 battery are not harmed in the process.

orion-tr smart
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1 Answer
Mike Dorsett avatar image
Mike Dorsett answered ·

from your statement "Alternator 56A total, 15A net dedicated" I would take that to mean of the 56A that the alternator is rated at, the engine electronics is using 15A, leaving 41A for charging other batteries. I'd use the Argo Fet to parallel the batteries for charging when the engine is running.

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