Cobaltchat.com

So it's time to replace the battery on my 2005 226 with the 350 MAG MPI. I had an exide AGM that lasted 6 years and was mainly used as a starting battery since there was not much use when the engine is shut off. The sucker weighed over 60 lbs and was a major pain to put in and take out. I am looking at the Ionic Lithium 12V S9 | 1400 CA | LiFePO4 Marine Starter Battery + Bluetooth and reached out to Mercruiser to see if they saw any issues with the charging system and LiFePo4 batteries. They were non-committal and said it was up to me to determine if it would work with the charging system. I have reached out to Iconic to see if they have any insight but wanted to see if anyone here has used a LiFePo4 battery as a primary starter battery and whether there were any issues.

There isn't much in the way of "intelligent" charging in a typical boat - I'd reach out to the battery company and see if they recommend doing anything special beyond simply connecting it to the alternator and starter like a regular battery.

John

Thanks John, I have reached out to them. I was also hoping for some real-life experience, not just what a manufacture might say.
Mike

Do not just connect your Lithium to the alternator. Lithium requires a special charging profile that an alternator does not provide plus it incorporates a BMS which shuts off current from the alternator. Shutting off current from the alternator will most likely blow the regulator. What is needed between Alternator and Lithium is a is a DC/DC convertor/charger which will take the power from the alternator convert to a charging voltage suitable for the Lithium plus a current sink that when the BMS kicks in it sinks the alternator current. Until a battery company can offer this solution I would stay away.