'99 Mercury 175 EFI battery ???

[Jsbowhunt]

S/N # 0G840335 '99 Mercury 175 EFI

Having a difficult time deciding on batteries. Have a couple AGM's from my previous boat installed now but losing reserve capacity even when charged. Apparently, Mercury only recommends flooded lead acid batteries for my engine due to the Stator charging system. My concern is I run three fish finders, a 360 transducer, live well pumps and two Talons off my start batteries. I currently run two AGM's but on my last trip I smoked my rectifier/regulators. So new regulators are installed and I want to replace my old batteries but not sure running two Flooded Lead Acids in parallel will keep up with my load.
Current set up is;
2 - Interstate 31-AGM7 batteries
CDI stator, 40 amp
2 - CDI rectifier/regulators
Power Pole Charger ( charges start/electronic batteries and 2 36V Lithium's for the trolling motor)

I would love to just put Lithium batteries in to save weight but Mercury and most battery companies don't recommend it (with the exception of Monster Marine who said "we have ran them on older motors with stators for years without issues. Still currently doing so")

Thought please ........

I have also posted this on the 2.5 section

[yam911]

Your type of charging system is what I will call a permanent magnet alternator. Or a flywheel alternator. As all alternators have a stator.

Mercury does recommend lithium batteries with other Mercury models that have a permanent magnet alternator/flywheel alternator. Not sure why Mercury recommends other models and not your model. It may do with the fact that your R/R's are air cooled whereas the later ones are water cooled.

All Yamaha outboard motors use a permanent magnet alternator/flywheel alternator. Many are using lithium batteries. I suspect that Monster Marine is correct.

[jrh_67]

I went with all lithium for the trolling motor and dedicated electronics battery but stayed with lead acid for the cranking battery. I was advised by Joe54 on this forum to NOT use a lithium on my motor and he knows more about these older mercs than just about anybody so I'll take his advice.