Inverter Battery Bank

dtfeld

dtfeld

Water Contrails
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Jun 5, 2016
5,551
Milton, GA
Boat Info
410 Sundancer
2001
12" Axiom and 9" Axiom+ MFD
Engines
Cat 3126 V-Drives
Looking for input/feedback on where a battery bank and inverter would fit on a 2001 410 Sundancer. Im considering a 4x6v golf cart battery bank (wet cells) and a Magnum inverter.

I removed the molded cubby hole right next to the captains chair and there is a fair amount of space between the inside liner and the top deck. I think enough room to get the 4x6v golf cart batteries in there. I ordered a battery box off Amazon to see what will fit.

The Next question is ventilation. The area in question has several large holes leading up into the arch and down into the engine bilge. How much ventilation is required?

The final question I have to answer is where to place the inverter. They do not recommend placing it in same location as batteries due to gas produced.

Any body install an additional battery bank on a 400/410? If so, where? Or, did you beef up the house bank and call it good? Pictures would be awsome.
 
use the generator , pretty sure a vessel that size would have one from the factory.
How much ventilation is required?
Enough to dissipate any explosive hydrogen gas produced
 
Dave, I haven’t looked in there since I first got the boat, but the removeable panel behind the pedestal for the helm seat might have the space you need.
You’d probably have to temporarily remove the base and seat to get some working room.
 
Bt Doctur said:
use the generator , pretty sure a vessel that size would have one from the factory.
How much ventilation is required?
Enough to dissipate any explosive hydrogen gas produced
Click to expand...


Have the generator, just sounds like a Farmall tractor, going to redo muffler over the winter to cut down on the noise. Vibration is another issue. Really detracts from a peaceful experience.

This is to run the coffee maker microwave, TV's and outlets for phone charging without starting the generator using Ttmott's schematic. I may install the AGS if we use the thing alot, but not sure its necessary, I can always manually start the Genny.

However, not much info on how much ventilation is required. I think I could add a vent hole at the back for additional air movement.
 
JVM225 said:
Dave, I haven’t looked in there since I first got the boat, but the removeable panel behind the pedestal for the helm seat might have the space you need.
You’d probably have to temporarily remove the base and seat to get some working room.
Click to expand...

Do you have an inverter on board?
 
B22A55B6-9CC0-42B5-BF66-56046F5533D3.jpeg
Dave I used 2 of these similar boxes for 4 6v batteries I put them in front of my motors and I have to say they require a lot of room.
I used lifeline AGM batts so venting is not a problem.
Also install the Inverter inside and not in the ER
How about a closet or storage that touches the Bulkhead ?
Is there room in the ER for the batts?
The Inverter has a fan but it should be located somewhere cool and dry.
 
Havana Shamrock said:
View attachment 59917 Dave I used 2 of these similar boxes for 4 6v batteries I put them in front of my motors and I have to say they require a lot of room.

I looked at that exact box, but I think its to big. The 410 w/ CATs is pretty tight in the ER. I could fit 2 of those on the engine room floor between the engines, but I'm afraid I couldn't get to the service points. As a secondary option, I'm looking at 4 individuals, possibly in the gunwale (room permitting). Needs to be servicable.

I used lifeline AGM batts so venting is not a problem.

That would solve the venting problem, but create a budget problem!! I was trying to get going with wet cells, first year of ownership has been a ball buster lol!

Also install the Inverter inside and not in the ER
How about a closet or storage that touches the Bulkhead ?

I have to find the room for batteries first, but I'm considering the aft cabin for the inverter itself, possibly under the aft berth (I have to look at access), or behind the couch (distance to batteries becomes the issue).

Is there room in the ER for the batts? - Possibly, distance to the inverter is then the issue.

The Inverter has a fan but it should be located somewhere cool and dry.
Click to expand...
 
I know your boat is very large, but that is a lot of weight to be topside and the deck underneath may not like the 400lbs or so you are talking about. I would try for a bilge location even if it means two smaller battery boxes. I have 2x6v golf carts and they work well. My inverter is a bit undersized. You may want to go for a combination inverter charger with lots of power if you are going to use it to run coffee maker and microwave. They pull a lot of power.
 
Weight at that location is a good consideration...will consider that as well. This location is pretty beefy, looks to have 3/4" marine ply covered in fiberglass. Structurally, I'm not concerned, but wonder if that would tip the boat significantly.

Currently the space on starboard is empty, the port side has a fridge, an AC unit, and some other equipment from the factory, all that probably wight about 200 lbs.
 
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You will want to minimize the 12v or 24v cable distance from the inverter to the batteries, so if all can be in the bilge it will be easier. The cables to run 4000 watts are pretty beefy and voltage drop is a lot if you put them too far apart. The 110v side is not distance dependent.
 
Creekwood said:
You will want to minimize the 12v or 24v cable distance from the inverter to the batteries, so if all can be in the bilge it will be easier. The cables to run 4000 watts are pretty beefy and voltage drop is a lot if you put them too far apart. The 110v side is not distance dependent.
Click to expand...

Correct. This is from the Magnum instructions, mentions not to install in the same place as batteries.

"Close to the battery bank – The inverter should be located as close to the batteries as possible.
Long DC wires tend to lose efficiency and reduce the overall performance of an inverter. However,
the unit should not be installed in the same compartment as the batteries or mounted where it
will be exposed to gases produced by the batteries. These gases are corrosive and will damage
the inverter; also, if these gases are not ventilated and allowed to collect, they could ignite and
cause an explosion".

Hell you wonder how it even possible to mount these things lol.
 
dtfeld said:
This is to run the coffee maker microwave, TV's and outlets for phone charging without starting the generator using Ttmott's schematic.
Click to expand...

Keep in mind that 4x6V golf cart batteries won't give you a ton of running time for a coffee maker or microwave, particularly if used in combination with each other and other loads. You will be running your generator to charge the inverter bank anyways. The generator run-time will be less to power those appliances directly, than it will be to replace the energy to the batteries that was required for the same appliance use.

A coffee maker is likely around 6-7A at 110VAC. A microwave 10A or more. This translates to almost 60A DC for the coffee maker and almost 100A DC for the microwave. At those draws your batteries fall way down the derating curve...even worse if they are hot. A 100Ah or 200Ah flooded battery will achieve a lot less than 100Ah at high discharge rates.

Now, you effectively have two 12V banks, which cuts the draw in half, but it would be interesting to look at the discharge curves for the batteries you are selecting to see how long they will run. You also need to considering inverter efficiency.

Note you can charge cell phones directly from a 12V source without converting to AC then back to DC again. TVs can be run with small, local inverters, especially with the newer, energy efficient ones.

Just some food for thought...
 
I'm planning to install these Mastervolt 12/5000 LI batteries. Note that you can drag them down to 80%DOD; AGM and lead acid need to be around 40%DOD to prevent damage and they are good for a minimum of 3500 cycles at 80%DOD which in real life is around 10000 cycles at a more realistic 30%DOD. What that means is 360AH is like 720AH in a lead acid battery. So this is comparable to three 8D lead acid batteries which would weigh 462 pounds but all at 128 pounds. Down side is they are a bit on the pricey side at $3100 each but they will be the last battery you will buy; in that light they end up cheaper than lead acid/AGM (service life/AH). The third significant benefit is they can be charged up to float at an amazing 500 AMPS. So at a more realistic 100 amp charge and at say 30%DOD you will only need to charge for about an hour to be fully charged. They also make a 12/2500 which is 180 AH. The really good thing about these modern LI batteries is they are made with the much more stable Lithium Iron Phosphate chemistry and have the Battery Management System (BMS) fully integrated with the battery. There is a fly in the ointment as always - should the BMS take the battery off line during bulk charge there is a possibly the alternators will self destruct or if the AC charger is on there could be a significant voltage spike and fry the boat's electronics. Most installations have a small AGM battery in parallel to act as a buffer should the LI battery trip off line.
Mastervolt LI 12/5000 battery specifications -
Nominal battery voltage 13.2 V
Nominal battery capacity 360 Ah
Nominal battery energy capacity 5000 Wh
Cycle life 3500 cycles at 80 % DOD at 25 ⁰C, max. C3 charge and C2 discharge (for batteries produced from December 2017)
Max. charge current 500 A (1,4 C)
Continuous discharge current 500 A (1,4 C)
Peak discharge current 1800 A (5 C) voor 10s
Battery monitoring integrated
MasterBus communication yes
Battery terminals M8
Mounting position upright or either long side
Max. outer dimensions (incl. terminals/grip handles), lxwxh 622 x 197 x 355 mm
24.5 x 7.8 x 14.0 inch
Weight 58 kg
127.9 lb ​
 
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All true, but I think the ease of use makes up for it. I run the genny a lot, but again, I'm looking for peace and quiet when I get up a 6:30 and everybody else is still fast asleep. We'll still have to fire the genny up for running the stove and AC if needed. But in N Ga in all but the hottest weather, not much A/C is required, and if I can get a breakfast and lunch out of the batteries while at a nice secluded cove/beach, it will be very worthwhile upgrade and mission accomplished.
 
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ttmott said:
I'm planning to install these Mastervolt 12/5000 LI batteries. Note that you can drag them down to 80%DOD; AGM and lead acid need to be around 40%DOD to prevent damage and they are good for a minimum of 3500 cycles at 80%DOD which in real life is around 10000 cycles at a more realistic 30%DOD. What that means is 360AH is like 720AH in a lead acid battery. So this is comparable to three 8D lead acid batteries which would weigh 462 pounds but all at 128 pounds. Down side is they are a bit on the pricey side at $3100 each but they will be the last battery you will buy; in that light they end up cheaper than lead acid/AGM (service life/AH). The third significant benefit is they can be charged up to float at an amazing 500 AMPS. So at a more realistic 100 amp charge and at say 30%DOD you will only need to charge for about an hour to be fully charged. They also make a 12/2500 which is 180 AH. The really good thing about these modern LI batteries is they are made with the much more stable Lithium Iron Phosphate chemistry and have the Battery Management System (BMS) fully integrated with the battery. There is a fly in the ointment as always - should the BMS take the battery off during bulk charge line there is a possibly the alternators will self destruct or if the AC charger is on there could be a significant voltage spike and fry the boat's electronics. Most installations have a small AGM battery in parallel to act as a buffer should the LI battery trip off line.
Mastervolt LI 12/5000 battery specifications -
Nominal battery voltage 13.2 V
Nominal battery capacity 360 Ah
Nominal battery energy capacity 5000 Wh
Cycle life 3500 cycles at 80 % DOD at 25 ⁰C, max. C3 charge and C2 discharge (for batteries produced from December 2017)
Max. charge current 500 A (1,4 C)
Continuous discharge current 500 A (1,4 C)
Peak discharge current 1800 A (5 C) voor 10s
Battery monitoring integrated
MasterBus communication yes
Battery terminals M8
Mounting position upright or either long side
Max. outer dimensions (incl. terminals/grip handles), lxwxh 622 x 197 x 355 mm
24.5 x 7.8 x 14.0 inch
Weight 58 kg
127.9 lb ​
Click to expand...


Holy Cow!!! They'll cost as much as my boat is worth lol! Those are a very awsome battery technology, but I think overkill for my purposes. If I can vent the battery area, I'm going to start with the Costco Flooded, if not I'm going to have to buck up to the Sealed AGM's Trojan has several lines with various life spans, so there is a balancing as to power available, DoD and weight and as always the almighty $$$.

Since I dont know exactly how we'll use the system, other than what I've calculated in my spead sheets, I think $400 for batteries is acceptable losses if its not exactly as I planned, and I can re evaluate when those crap out.

https://www.trojanbattery.com/markets/renewable-energy-re/
 
ttmott said:
Most installations have a small AGM battery in parallel to act as a buffer should the LI battery trip off line.
Click to expand...

I follow an interesting sailboat vblog called "Sailing SV Delos" (does admitting this incriminate me in some way, or cause a rift in the cosmos by fracturing generally accepted stereotypes?). They did a full LI upgrade that is pretty interesting.

Their videos are here:

Nothing earth-shattering, and likely nothing new, but they have interesting real-world experience.

Their install includes the buffer / float you speak of...
 
If my math is right, thats about $12,000 in batteries!! Nice. Makes a cup of Starbucks a day seem cheap!
 
Dave, my 4 6 vdc AGM batts have run everything on my boat inc microwave, coffee, TVs 110 vac fridges, computer, camera system you name it for over 17 hours. The Inverter /charger also runs the house batt charger so we can always start the motors. The lifespan of our batts is somewhere around 7-8 years I’m told so in 8 years if I buy new ones it’s still cheaper than LI batts.
My Inverter shuts down when they reach around 40% which has never happened yet .
I have also changed every single light in my boat to LED my draw went from 30 amps to 3 amps running every single light as a test.
If you can do the install do it you’ll never regret it.

Ps don’t skimp on buying good wiring and connectors.
 
dtfeld said:
Do you have an inverter on board?
Click to expand...
No. Thought about getting one but decided that I really don’t have a need for it, especially when I started thinking about what it would cost in money and space.
For the way we use the boat: If I want power on the hook or away from the dock I just run the generator. Mine is pretty quiet.
Tough to get an exact number, but so far I have figured that it only burns about a half a gallon an hour with both AC units, fridge, TV, charger, etc. running.
 
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This will be my second inverter install. Putting a lot of energy and engineering into planning this out and getting best bang for the buck. Still need a lot more measuring and contemplating the pros and cons of where everything goes. You would think its easy in a 41' boat. But every engineered system has its compromises.

This forum and the folks on here have been a huge help!
 
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