Lithium Batteries / charger for Boat

[SkunkedAgain]

I've had several boats over the years and currently have a Thunderjet with two outboards and a 24v electric motor.  I have a two bank charging system for the two AGM electric trolling motor batteries.  Each outboard has it's own marine, wet cell cranking battery.  I have never had, or seen a need for a charger for my outboard cranking batteries.  As long as one of the outboards is running, it's cranking battery is being charged by the outboard.  I typically get 7 years plus out of my cranking batteries and I have never used a charger on them - ever.

The only issue that I'm aware of with lithium batteries and cold weather is that you can not charge them when it is cold.  If they are charged, they work just fine in cold weather.  My Vexilar has a lithium and has worked just fine in -20 degree weather.

I am not impressed with the lighter weight of lithium when it comes to being used in a fishing boat.  Your outboard could care less if you carry a few extra pounds of wet cell battery weight.  And I seriously doubt you can tell the difference in your boats performance by shaving a few pounds of battery weight.

Good quality marine batteries will give you many years of excellent service if properly maintained.

But hey, it's your money.  Spend it on whatever you want.

Hey Bob, I think you put your finger on the cold issues with Lithium, I think the recharge is probably the issue.  Now you mentioned this, I had heard that you need to take your batteries inside to charge during the winter, so I'll bet this is the concern with them... Wonder what temp is considered cold where you need to do this???  

As far as recharge of cranking battery, I have my electronics on that circuit and I think I might need to change this, but that is typically what runs my cranking battery down and it's not an every trip deal, but once in a while and mostly after the boat sits for awhile, that I have to recharge that one... Plus that battery is old and tired and time to replace it...

On the AGM/Lithium cost issue, I was looking at both when I decided to go Lithium, AGM was $189 to $239 lithium and I had heard 5 year life verses 10 plus years so I figured $50 for 5 years was worth it.. Weight only plays in when installing and working on the batteries to me, not the boat performance, it's a save my back issue to me.  You know I'm cheap, so I likely wouldn't spend extra just to be trendy... I think your dislike of the lithium is probably tied to the crazy price that they used to be, but now they have dropped to close to AGM prices I'll bet more will start to adopt them... I couldn't justify $500 per battery, but two for that price put me over the edge... We'll see, maybe I'll be eating crow, but sounds like quite a few folks really like the lithium, so I hope to be happy as well... 

Thanks for the input Bob, appreciate that insight... Jeff