Lake Michigan Cruising - whats the right battery?

[jpeac2]

All-

About to replace my batteries for the second time in three years due to what I believe to be incorrect off-season maintenance. I am trying to understand if it is worth it for me to invest in better batteries / different technology for what I use the boat for.

Background:
- 1997 Beneteau Oceanis 35'
- Use mostly for some day cruising in Chicago
- Usually do 2 trips across the lake and then anchor out for 2-3 days and then sail back. During these trips I do not have any requirements to keep the fridge on so it is mostly just leaving the anchor lights on and starting the engine.
- We do a 10-15 day trip up into northern lake Michigan where we will stay out of harbor/anchor out for up to a max of 4 days at a time. In these scenarios we will try to use the fridge to keep everything cool. We also may run the motor during the day if we are moving between destinations.
- All led bulbs in the cabin
- Fridge is a alder barbour cold machine

Currently the house bank is two duracell 75ah FLA. Not sure what the starter is but its in good shape. Attached a picture of how the duracells are setup.

6CD8A3B8-A704-4121-871F-6B9890671766 by fortfunfosho, on Flickr

My questions:
1. For the relatively small amount of cruising we do where we go extended days with actual battery use - do I need to move to a bigger house bank?
2. I am not great with off-season maintenance and I think that may have contributed to the degradation of these batteries. For this reason is it worth it to spend more money on a nicer battery to mitigate this? Or do I just come up with a better plan to make sure these have better maintenance?

Any general thoughts based on what I have outlined?

I can go buy two more of those same duracells for under $200 and then most likely be in the same spot 2-4 years from now. Or is there a different path I should pursue?

[ctl411]

I would go with regular deep cycle. Also make sure to mount battery in port starboard orientation.
Google "pbase battery orientation", explained very well in this article.

[Stu Jackson]

Originally Posted by jpeac2

>>>>>>>>>>>>>>>
- do I need to move to a bigger house bank?>>>>>>>>>>>>>>>>>>>

Yes.


For your cruising plans at least 200 ah bank, better yet larger.


You may not be aware of this:


Beneteau Wiring Diagrams - Maine Sail's corrections - Just in case you have a friend with a Beneteau and want to help him with his snafued wiring Reply #8

https://forums.sailboatowners.com/in.../#post-1456512

[jpeac2]

Stu -

I was NOT aware of that. Thank you for sharing! Filed for reading tonight!

Thanks!

[valhalla360]

I wouldn't dump a lot of money into a bigger battery bank until you sort out maintenance. Otherwise, it just means a bigger bill the next time the batteries fail.

For your use, I would suggest muddling thru running the engine for a bit each day. You likely will never burn enough fuel to justify the upgrade cost and we aren't talking enough hours to have any noticeable effect on the engine life.

If you get anything, maybe a small solar panel, so you have to use the engine less to recharge.

[John_Trusty]

The basics are that lead-acid batteries are killed in the extremes away from 100% charge - over charging or under charging shortens life. I don't know what your maintenance program is for winter, but in cold weather, they will not self-discharge much. You can leave your fully-charged batteries (disconnected) for months on end and still have over 90% in four cold months. If you get particular, hit them with a full charge for a day each month, and check the water afterwards.

[bstruebing]

I move mine to the basement with a full charge, keep off floor with a 2x6, trickle charge each one half way through. My uncle convinced the whole family that it was fine to leave them in the boat over the wonter. The whole family tried it and the whole family had to replace batteries in the spring. FAIL!

im in lake st. Clair, same winter

[ArmyDaveNY]

There are many possible reasons for batteries to die early. Check out the link below and you'll see one reason that many are not familiar with. It is a very interesting discussion of the proper orientation for a battery in a mono hull sailboat. In a nutshell, incorrect orientation will lead to premature death due to the plates being exposed to air when healing. It's a short but interesting read.


https://marinehowto.com/installation...ries-on-boats/