New Firefly batteries: Other recommended upgrades?

[Patches]

After a lot of thinking and reading, I'm leaning toward purchasing two Firefly Oasis batteries for my house bank. Would like to do the upgrade work in December and January, and I'm trying to figure out what else I'll need to make the upgrade.   I pretty much have the OEM electrical system on my 1990 C34.  This includes:

1. Internally regulated Prestolite 51 Amp alternator;

2. Two group 24 deep cycle Interstate batteries;

3.  Original Newmar charger;

4.  Charging via alternator goes through the selector switch on the panel, then to the batteries.

I don't have a lot of electrical demand.  As yet, no refrigeration, but I'm thinking of going with an Engel portable fridge/freezer strapped to the bench seat in the aft cabin.  It would replace the Igloo Cooler already there which I use when cruising for a couple of weeks in the summer.  Other than that, no windlass, no radar, and all interior lights and anchor light have been switched to LED bulbs.  I usually use the ancient ST 4000 wheel pilot (still works!) only when motoring. I have the original B&G Focus depth sounder, but am happy to use the handheld Garmin 78 for just about everything else.

So, the reason for the switch to the Firefly batteries is more usable amps, their ability to function in a state of deeper discharge, and the increased number of charge cycles.  No electrolyte monitoring, no need to carry the distilled water or measure specific gravity, no need for battery boxes, and fewer concerns about heeling.  And I know this comes with the need for a lot of other new equipment and upgrades in order to carefully charge the new Firefly AGMs.

Based on what I've read, I need (at a minimum):

1.  A new alternator wired for external regulation (small frame to fit on my M25xp);

2.  a new external regulator which may need to be programmable to make sure the Fireflies get what they need from the alternator;

3.  a new AC battery charger;

4.  a new Battery monitor (Victron ?).

5.  assorted battery cables, wires, and fuses.

So, I would appreciate any advice (or cautions) on filling out the equipment list above--or suggested additions to it.  I would like to support Mainesail with my purchase dollars.  Eventually, I would like to add about 200 watts of solar too. 

Thanks in advance for your feedback!

Patches

[Jim Lucas]

Hi Patches,

I am not an electrical expert by any means but, it sounds like you're heading in the same direction I did. I have 3 x Firefly's for my house bank and an AGM for a starter. I upgraded to a Balmar voltage regulator and added a Victron (Blue-tooth) battery monitor amongst other upgrades...

I could go on but will say, it wasn't cheap but was a good (IMHO) long-term investment. Others, do VERY well with different setups without the hefty expense.

Your boat - your call.

Cheers,
Jim

[Stu Jackson]

Patches, two major things are missing from your presentation:
1.  How you use your boat:  day-sailor, marina hopper, or regular long-duration cruiser/anchor-out.  Do you get to plug in reasonably often or not?
2.  Your energy budget:  without a fridge, but with an Engel, it will most likely be less than 100 ah per day.

Based on all the information in the Electrical systems 101 Topic, I believe you are heading in the wrong direction and doing it backwards.

Your major issue is NOT what technology you use to store the energy, but rather the production and electrical distribution system.

By switching to Firefly batteries, you will increase the demand on your production because of the higher acceptance of those batteries.  Your system will not support it.

In terms of priorities, what you should do to improve your system is to first remove the AO from the switch and move it to the house bank.  Either buy a combiner or use the B on your switch to charge the reserve or start bank.  The "Why" of this is already explained in the Electrical systems 101 Topic.

Then add your solar, and increase your AO with a new alternator and external regulator.  Resize your AO wiring to suit.

Only then consider changing battery technology.  I don't think you need anything more than wet cells, whether it's 12V or golf carts.

Much depends on how you use your boat, but regardless of that answer you have to improve your production and distribution system first before you can even begin to obtain any storage advantages.  As you said, only a single cruise a year doesn't justify all this.

[Stu Jackson]

Oddly enough, just today a skipper on sbo asked pretty much the same question.  He already has solar, and most likely a fridge. 

Maine Sail answered:


Question:   It is time to replace those old 4d batteries that came with my boat. I recently read about Firefly Carbon Foam batteries. Does anyone have any experience with these? They are a type of Lead acid AGM battery that has some really favorable characteristics. I wonder if I can use my existing charger setup with a Carbon Foam battery. If so, would I just use the AGM charger setting? This question also applies to my solar MPPT controller as well. Can Carbon foam batteries be connected to the alternator output like a conventional battery? Ideally, I would like to use Carbon Foam for my house batteries and a regular AGM for a starter battery. Can these types be mixed in this way?

Answer:
As one of the first marine installers in the US I can tell you that every bank we've installed still has at least 97% of it's original Ah capacity. I cannot say that about any battery other than LiFePO4.. They do however need proper charging. You will need 14.4V absorption and 13.2V - 13.4V float (13.2V is better for float). You'll also need temp compensation for all charging sources including solar, alternator and battery chargers. At least one of your charge sources should be able to achieve at least .3C (30% of Ah capacity) but .4C (40% of Ah capacity in charge current) is preferred. Whether they can be charged in parallel will be based on the start batteries charge parameters. They also suck a lot of power from an alt, and can burn them up, so an externally regulated alternator system is really the best way to deal with this.

____________
-Maine Sail / CS-36T

MarineHowTo.com (LINK)

My Forum - Musings With Maine Sail (LINK)

Bed-It Butyl Tape (LINK)

[Stu Jackson]

I also referred that skipper to this thread on www.cruisersforum.com:

https://www.cruisersforum.com/forums/f14/firefly-battery-operational-user-notes-238410.html

Please recognize that that discussion veers off into a lot of tangents, some of which are helpful, and some are just dead wrong.  An example is how the Balmar external regulators work, i.e., timers or voltage checks. Another is using solar first and then a generator later in the day [one should use the generator for bulk charge first].   The lack of understanding of how BMs work is truly frightening after all the years since I wrote the Gotcha article [2011!!!] and Maine Sail did his a few years ago.


And also that those guys are discussing real "out there" cruisers, not one week a year folks.

[Patches]

Thank you for the replies!  I was already going to make the upgrades suggested by Stu (everything is original and 30 years old). 

Given the quoted comments from Maine Sail re charge profile for Firefly batteries, looking for specific recommendations as to charger, alternator, monitor, and external regulator.

Jim:  Which Balmar external regulator did you go with? 

Patches

[Stu Jackson]

Thank you for the replies!  I was already going to make the upgrades suggested by Stu (everything is original and 30 years old). 

Given the quoted comments from Maine Sail re charge profile for Firefly batteries, looking for specific recommendations as to charger, alternator, monitor, and external regulator.

Jim:  Which Balmar external regulator did you go with? 

Patches

Patches,

The only "main line" regulators that seem to be very popular are the Balmars.  They make two, and the differences are included in the ES101 topic:

Differences between Balmar MC-614 and ARS-5 Regulators 101

http://forums.catalina.sailboatowners.com/showthread.php?t=160744&#post1102540
http://forums.catalina.sailboatowners.com/showthread.php?p=1053410&highlight=ars-5

There are others and a Google search would most likely find them, but Maine Sail suggests the Balmars are quite good.

charger, alternator, monitor:

Charger:  Sterling or ProNautics:  these links discuss not only the wiring but the advantages of these two new identical chargers

Wiring a new charger From Maine Sail:

http://forums.sailboatowners.com/index.php?threads/marine-battery-chargers-installation-tips-considerations.136765/#post-880275
and
https://marinehowto.com/installing-a-marine-battery-charger/

Alternators:  this changes all the time, but ES101 covers it, too.

Monitor:  The Victron is the better coulomb counter, others prefer the Smart Gauge, and there are two of them.  Also extensively covered in ES101.

[Patches]

Thanks to all for your input!

Just ordered all the major pieces from Maine Sail--who recommended the following for Firefly batteries given my engine-- for the electrical upgrade to my 30 year old OEM system.  Ended up ordering the following:

1.  Victron 614 battery monitor;

2.  Compass Marine 105 amp, externally regulated, small frame alternator for Universal M25xp;

3.  Balmar MC 614 external regulator with alt and battery temp sensing wires;

4.  Sterling Pro-charge Ultra 12v-60amp battery charger.

FYI, the cost to go with the above equipment to support the Firefly batteries, vs the cost to go with a 72 amp, externally regulated, alternator and a smaller 12v-30amp charger to support a lead acid battery upgrade was <$250.  After considering the increased performance of the Firefly technology, and cost/amp hour over the long term, this upgrade made sense for my purposes.

Was also happy to finally make a bigger purchase from Rod (Maine Sail), whose prices are exceedingly fair.  I've been grateful for his many "how to" resources and clear explanations of various matters since going to an inboard a few years ago.

Patches

[Jim Lucas]

Hi Patches,

I think you'll be immensely happy with this upgrade as I am. 
I believe it was worth every penny spent but, as a few have stated, it depends on your cruising plans. I wanted the ability to go for weeks at a time and concede that may only be 1 or 2 trips/year. But, I'm ready to go whenever the opportunity arises!! 

[Stu Jackson]

Thanks to all for your input!>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>

I've been grateful for his many "how to" resources and clear explanations of various matters since going to an inboard a few years ago.

Patches,

That's great.  That list is exactly what I would recommend, too.  You'll be very, very happy.

Glad the material we've gathered over the years from so many contributors helped you along also.

Can't wait to hear and see how it all pulls together.  Just for grins&giggles    have you worked up a wiring diagram yet?

[waughoo]

This will be a notable improvement in your battery situation.  I am currently reviewing a battery work over for my boat.  I REALLY want to do lithium and probably will, but the first step is to set up a dedicated engine battery first.  The house bank I inherited with my boat is three G27 interstate deep cycle FLA.  They are not likely a good solution at all given what I'd like to do with it, but I will probably combine the three batteries into a single bank (presently one is reserved as a start battery) for a while till I can sort out the infrastructure for an upgrade to a larger house bank.

Do let us know how it goes with your Firefly installation and surrounding upgrades.  I'm anxious to hear how it worked out.  Firefly batteries are also on my short list to consider.

[Patches]

Will definitely be posting about the new setup.  My charter season doesn't end for the year until December 1, when I will first undertake the new prop shaft/coupler/and (still undecided) PSS or new stuffing box.  Then will start on the electrical upgrade, and get that sorted before the season resumes around February 1.

Very excited for these upgrades!

Patches

[Bill Shreeves]

As it tuns out, because my alt went South, I'm in the process of figuring out how to mount the Compass Marine 105 amp to my M25XPB.  The existing arm does not work and neither does the Universal arm from Compass Marine based on the template print-out available.  Short of an easy answer from someone on this board, this is my approach:

I temporarily installed the 105.  With the existing arm mounted, I over-laid the template print-out of the universal arm and adjusted the template to a position that appears to be a good fit.  I taped the print-out to the old arm then removed the arm with the template attached.  I took this and laid it over a piece of starboard and cut it out the new arm along with faring the junction between the two arms.  I'll take the mock-up to the boat this weekend to see how it fits.   If good, I'll take it to a machine shop to fab in 1/4" steel.

BTW, the 105 has to be rotated much farther to Port or clockwise more than the original alt because the terminals on the back of the alt hit the manifold.  So, along with a new arm, I'll need a different size belt and keep the belt length in mind as I mock-up the position of the alternator with the new arm.

Ideas?

BTW, I also picked up two new Firefly's a couple of weeks ago because my house batteries need replacement.  I installed a Balmar SG200 monitor last year and I have a 3 year-old ProNautic 40 AMP charger that I'm sticking with for now.

[Patches]

Jim:

I take it you replaced battery cables as part of your upgrade to the Firefly house bank?  If so, what size cabling did you go with?

I'm replacing the old 4 gauge and moving the battery switch to the side of the battery compartment much like Jon did in his excellent write up of his electrical system upgrade in 2015.  He upsized to 1 gauge. The Fireflies, being Group 31 batteries, fit nicely in the battery compartment.  I'm planning to wire two in parallel, which leaves plenty of room for bus bars, fuses, and switches.

Makes sense to me to run the cable to the starter--like he did--under the cabin sole and up through the holes already drilled for the hot/cold freshwater lines for the head sink (on the port side of the engine).  Because I had already re-routed those supply lines as part of moving the water heater to the  locker aft of the Nav Station, and have no water heater crowding to contend with under the galley sink on the way to the battery compartment, the run of the cables looks pretty straight forward.

Same with running new cables up to the panel. 

Thanks,

Patches

[Rick Roberts]

I had the Oasis Firefly battery for a bit and I did like them. There is a fair amount of voltage sagging. Depending on your budget and how long you are considering keeping your boat. There's a new alternative to Lithium, there's a company called Battle Born making these LiFePo4 batteries that are super safe, 30% of the weight and 100% DOD.