ODIN
TECH GOD!
Official Answer
Typically, we recommend if your motor is 250hp or bigger to get a Norsk Lithium 12V 180AH Heated Starting battery. If your motor is under 250hp, but you are going to be running a variety of electronics, we would also recommend a 12V 180AH Heated Starting battery. If your motor is below 250hp and you are not running your electronics using the starting battery, we would recommend the 12V 120AH Heated Starting battery.
**If you are running a Mercury Pro XS outboard that is 200hp or larger, we suggest getting a 12V 180AH Heated cranking battery. This outboard has a high-output alternator that can exceed the accepted amp draw of a 12V 120AH starting battery.
Answered by Odin TECH GOD!