Moving battery bank to galley

[C-Wolfe]

I will be moving my house battery bank to inside the cabin, my first thought was to move it inside the galley cabinet. The cabinet is quite deep and loosing some storage room in the very back might not be such a big deal after all, but that is still loosing some valuable storage room. My second option is to move the batteries to inside the pontoon, I have an access hatch to access the water pump and sump box. I already replace it for a smaller one to help make room for the batteries in the back of the cabinet, this can easily be undone and put the original hatch back in



I can move the water pump as far outboard as possible, as for the sump box, the shower was move to the cockpit and I just remove the water heater, so I can get that out, at least for now. If I need it back in the future, I can find a different location for it.



That location put the battery right next to the starboard fuel tank, I’m not too crazy about that, is that a legitimate concern or not? This is the main reason I’m reaching out to the C-Brats community right now. On my CD22, the batteries where very close to the fuel tanks as I think many others, but it still feel different then inside the pontoon of the tomcat.
So here is the full picture. I will be adding 2 Victron 18 amps dc to dc charger (one from each start battery), I currently have 2 AGM 100 AH group 31, I will keep them as long as they perform good but will consider switching to lithium when time comes to replace my house bank. I have a few switches, fuse block, beaker box in the cockpit lazaret the have a good amount of corrosion, I would like to move as much of those inside the cabin/galley cabinet as I can. That will hopefully reduce the maintenance on my electrical.



As Always, feel free to poke any holes in my plan and let me know what I might have miss. But as stated above, my main concern is the new battery location.
Thanks for any input .

[thataway]

I put an inverter AGM bank of batteries in the Tom Cat 255. I put them in the port cabinet under the aft seat, as far outboard as possible.

I would prefer not right against the battery tank. That leaves you with 2 engine start batteries--and maybe take a jump pack along. I also used the jump pack to power my inflatable boat pump, as well as an emergency back up for starting.

Why the DC to DC, unless you have the lithium? Because of the AGM?--or limiting the amount of current? Doing it now in anticipation of the LiFePO4? Be sure and set the Victron DC to DC to AGM charge profile.

Fuses? I agree on switches,& bus bars inside of the cabin, close to the batteries. Be sure the windlass is off the start battery, as well as the Wallas (if you have one).

Good idea, and execution of the plan.

[C-Wolfe]

Thanks Bob,
As of now, I can combine my starboard start battery to my house bank through a manual switch, need to remember to switch back while at anchor. I have no easy way to use my port engine to charge my house bank. Not my favorite way.
So yes, one of the reasons to add the dc to dc is to have charge coming from both engines. I also want to be able to control the amount of current going to the house bank, and I figure 2x 18 amps should be good for my usage. and I also want to be ready for LiFePO4.
As for the Wallas, on my previous CD22, it was connected to my house bank and it work fine for me. I’m often in remote location and would prefer to run down my house bank than my start battery. Same goes for the windlass, but while using it, I always have the engines running so I’m getting some charge. I do have the profish so I’m using minimal power while dropping the anchor, using more on retrieve but I’ll normally be running the engines for a bit after weighting the anchor. I also have a 9.9 kicker with a generator that I can run some when I start the Wallas in the morning and I’m not planning to move that day, but that is not often needed in my experience.

[thataway]

There were a very few days I needed to start the engine to get higher voltage for the Wallas. But with some boats it seems to be essential. (Maybe they have some corrosion which drops the voltage?)

With the li batteries, the draw of the windlass may be in excess of the amount of discharge allowed by the BMS. There are starting rated LiFePO4 batteries. On the other hand I have run a 2000 watt inverter off the Li batteries drawing as much as 200 amps off two 100 amp hour batteries😁) I have not used them. You could then keep the windlass circuit on one of the engine start FLA batteries if necessary. The windlass should not draw more than 60 to 80 amps in the Lewmar 700 series. (or even the 1000 series)

[C-Wolfe]

[thataway]

In my 255 there were several circuits where several butt joints were between the switch and the end appliance (shower sump pump, water pump for example). Several of these had a larger wire to a smaller gauge wire, with a larger crimp fitting. Properly a reducing crimp fitting should be used: For example a #14 wire to a #20 wire, should used a Blue to pink butt connector (14-16 gauge to a 18-22 gauge swage butt fitting. Below are various adaptor butt. connectors used to properly connect wires of different size groups.



Also you want to use a single wire of adequate size from the battery to the wiring on the Wallas stove. For the run in the C Dory I would recommend 10 gauge wire.

[WCF]

Most current bottom of the barrel 100Ah 12V LiFePO4 batteries have 100A BMSes.

Will Prowse and others on youtube have reviews you can watch to confirm the battery you want to buy can output 12V 100A for relatively long periods. Many of the cheap batteries will put out their full rating until the battery is exhausted.

Many of the newer inexpensive 200Ah+ batteries have 200A BMSes.

This was not the case 4-5 years ago.

I would not worry about the windlass unless you know for sure you are going to buy only one LiFePO4 battery and it will have a 100A or less output rating.

Just my opinion, but I would go to LiFePO4 now and enjoy the benefits rather than doing this work and having to re-work it later. Group 31 AGM batteries are usually around 65lbs each; that does not sound fun to lift in and out of that hole.

[thataway]

Agree with above. I recently purchased 4 LiTime 100 amp hour b atteries for just under $200 each. Amp per amp this is cheaper than many AGM. Will Prowse gives a good review of these batteries. I should be set up to see how they work with high loads in an experimental setting (running a 3000 watt inverter, with various loads.)

[WCF]

My current setup in my 25 is also LiTime - Two of the 230Ah Bluetooth versions. No problems even when maxing out my 2000W Victron Multiplus charging or discharging. They fit really nicely in the water heater cabinet on the 25.

I'm sure many other similar batteries are just as good, but LiTime's basic 100Ah "Mini" batteries were also very good to me and open up some nice packaging options.

It is getting harder and harder to go wrong with this stuff, which is good news for every C-Dory owner.

[C-Wolfe]

With a quick search, doesn’t look like I can get those LiTime ship to Alaska. It’s too bad because they look like a very good deal right now. Bob, I’m curious to know what your test shows.
WCF, how long have you been using those? What are your thoughts on it?

[WCF]

[thataway]

On the C Dory 25, I had two Li FeP04 Battle Born ($1000 each initially) 100 amp hours. I had a Sterling 30 amp DC to DC charger off the start battery of the Honda 150. I limited the output to be about 25 amps. (This charger was easily programable.) Most days running would bring the Li battery up to full or nearly full state of charge.

I have been using a "portable rig"--one Renology 100 amp hr battery, the Victron Orion 18 amp, running chest freezer. It is used on my RV or Ford Explorer. There is not problem with that lower output, since I am only using it on days I do a lot of travel--or on days with short runs, where I can be using a 120 AC mains power to charge in between trips to the store, or trips across country. .

[tsturm]

[KevinMc]

Great topic.I have a comment that might be helpful.With the Li Po4 and other BMS controlled batteries I would recommend an on post blow fuse in case of control failure and back feed.I have installed one 30A on each of my two 100 amp.JUST JUST IN CASE.A fire ( in the cabin area ) is a concern with Lithium and the further away from the fuel tanks the better. Coast Guard Regs are slow on this matter.I would consider all wiring a high maintenance item in any marine environment,weather inside the lazaret or cabin interior.
Also. if upgrading from standard batteries,always up grade the wiring.

[thataway]