Looking for an Inverter Bank Solution

[Jackie J V]

My inverter bank died at the end of last season - the very last weekend in fact. Three of the four 8D's pooched and they started venting gas... So now I'm trying to find the "best solution" to replace rather than simply replicate what I had before.

I had started a similar thread last summer, when I prematurely thought the bank had died (I guess it was an early 'last gasp' for the bank). See: http://clubsearay.com/showthread.php/52362-Comments-on-Best-house-Batteries?highlight=batteries if you're interested.

So here's what I've been investigating:
1. Lithium Ion
2. Golf cart batteries
3. L16 Floor Scrubber Batteries
4. Lithium Ion
5. Custom Industrial Solution

I have a few bucks invested in this boat and believe it or not, my inverter bank is a significant part of my enjoyment of boating. Probably my favourite boating moments are enjoying a coffee at anchor while sharing a sun rise with the loons. Very peaceful. But not so much if I don't have my coffee... then it's more like #*$&%!

My current configuration has four 8D's running through a Victron 5KW inverter (love the inverter by the way. I've had both Xantrex and Charles Industries before and I have much more satisfaction the Victron). The significant usage of the inverter bank is for the following: running the TV and PS/3 at night when the generator is off (stoopid teenagers), keeping the fridges running (I have a Sub Zero fridge and a Sub Zero freezer side-by-side that are 120V only) and making my precious coffee in the morning. I generally shut down most everything else at night (beer fridge and ice makers) to preserve the bank. Generally, I found that if I stick to a reasonable routine of running the generator a few times during each day to recharge, I can keep the bank going for an extended period. It's dicey though, and a few times I've gotten up to a depleted (i.e., <50% bank). It's generally best not to engage me in direct eye contact when that happens... Up in these parts, we don't run our generators over night and generally wouldn't start them up until 8am when other folks have arisen.

I'd appreciate hearing any recommendations you might have. So far, here's what I've found:

1. Lithium Ion. Pluses: Great capacity. Half the weight. Charges quickly. Minuses: Stupidly expensive. Finicky with voltage. Like to catch fire. (Think 787 Dreamliners) (Hmmm... Expensive, finicky and explosive - sounds like the Admiral - For God sake don't tell her I said that...)

2. Golf cart batteries: Proven solution. Reasonable price. Increased capacity beyond the 8D's. I'm told that 8 batteries will give me 928 amp hours for 560 lbs.

3. L16's: Even greater capacity than the golf cart batteries. Proven in industrial applications plus I had a couple of these in my last boat. I seemed to have to do an inordinate amount of desulfation (have to run an overcharging routine) on those batteries though. Minuses: Weight, cost, height (not a problem for me, but the taller batteries might prove a challenge in many boats - they were a bit of an issue on my last boat where they were tough to maintain). I'm told that 8 batteries would give me 1350 amp hours for 960 lbs - starting to get heavy.

4. Industrial custom: I'm still in learning mode here. Working with a local battery supplier for a custom built solution involving assembling a battery from 2V industrial cells. Here are some comments from the supplier from an e-mail:

I am looking at 2 options for you, either of which will fit into a case with a ~16” x 13” or less footprint and have an overall height less than 2 feet (although if we opt for using a lid, you will need some additional height for clearance). This could be done side by side in a single case or with 2 cases, but definitely with 2 x 12volt ‘packs’, so that there is some redundancy. The larger option will provide you with ~650Amp-hours @ 20 hr. rate and the smaller with ~ 550 amp-hours., getting you to around 1100 AH+ range. These would be based on an industrial cell with a 1500 cycle design life and we would equip them with a single point watering system and low level electrolyte indicator.

Additional information:
1)Weight approx. – 500-450lbs. (would be assembled by individual cells) (Note - I'm not sure if this is total or per x2)
2)Capacity is relative to weight, so I would suggest we have a quick conversation about this, i.e. the meter will read amp-hours accurately, so as long as the batteries get charged back it is ok to discharge to 80%....
3)The estimated footprint is each
4)The larger solution adds weight, probably slightly less per amp—hour cost.

Does anyone have experience with a more industrial solution? Any recommendations?

I will post anything else that I find and will post details on my final implemented solution.

Paul

 

[Four Suns]

Have you seen the price of LI 8D batteries?

http://www.simpleray.com/Lithionics-Lithium-Ion-12V-400Ahr-8D-Battery-p/60000-18.htm

400 Ah and 3000 cycles with 80% discharge is pretty impressive though.

I hear they are working really well in the Boeing 787.

 

[Jackie J V]

Gary - you jumped in as I was in the middle of my post. Those were my conclusions exactly - including the Dreamliner experience which sealed their fate. No LiIon for me - thanks.

Paul

 

[Jaws]

Hi Paul,

We can't help but notice what the sailboaters in Georgian Bay do. They stay out for long periods of time and few of them have generators but their overall power needs are much less than yours. The popular set up for the sailors is inverters tied to 6V golf cart batteries.

Maybe you are over-thinking this? Simple is good.

James

 

[Jackie J V]

James,
I certainly may be over thinking this, but what else is there to do when the boat is up on the hard? :grin:

If nothing else, it's a learning experience and at the end of the day, when I can't get my coffee in the morning, at least I'll know I tried...

Paul

 

[northern]

We have 10 six volt golf cart batteries for house power. They take 8 hours to charge from 11 volts at 140AMP rate. If we leave the ice maker on they are good for 3 days. Running the 8KW generator for 3 hours a day gives us enough power to keep all things running.
Model train people use lithium batteries. A friend said you will damage them if youover charge them.

 

[HUMPH]

My friend with a 560DB had 8 L16's but when he had to replace them he went with 4 and has gotten along pretty well. We only run the generators on the delta to charge batteries for boats with inverters. I don't have one yet so I run it whenever I need 120 VAC. A friend is a dealer so we get great prices on Trojan batteries. My J185h's were around $265 each.

 

[Jackie J V]

Interesting that I'm hearing a few folks recommending Trojan batteries (on this and the earlier thread). One of the other questions I had is, what brand should I choose? I was also looking at Surette/Rolls, which makes a good marine product. Any others with good experiences with a particular battery manufacturer?

Paul

 

[AMFM3]

Timely thread Paul. Thanks for posting. I'll be reading with interest.


Sent from my iPhone using Tapatalk

 

[hottoddie]

Interesting that I'm hearing a few folks recommending Trojan batteries (on this and the earlier thread). One of the other questions I had is, what brand should I choose? I was also looking at Surette/Rolls, which makes a good marine product. Any others with good experiences with a particular battery manufacturer?

Paul

On my last boat I used 4 Deka L16 in series/parallel wired to a 3000 watt inverter which would in turn be wired to a shore power/generator (boat had no generator) switch that would provide ac power the whole boat. I would go off shore power for 3-4 days and have plenty of power to make coffee, run tv and refrigerator. Batteries were 4 years old when I sold the boat 2 years ago and they are still in the boat today.

 

[Jackie J V]

Mmmm, Hottoddies... My father, God rest his soul, would always fix a hot toddie to ward off the cold...

Lot's of good input so far, thanks.

Paul

 

[HUMPH]

Trojan is a very reliable brand.

 

[ttmott]

Question, I didn't pick up on it in this thread, but is this house bank also used to start one of the engines? And if so how does this play into the battery selection?

 

[hottoddie]

Question, I didn't pick up on it in this thread, but is this house bank also used to start one of the engines? And if so how does this play into the battery selection?

In my case the 4 six volts that were the house banks were used to start the starboard engine. The port engine had it's own group 27 for starting it. If needed (I never did) I could jump start the starboard off the port thru the battery switches. Worked like a charm.

 

[Jackie J V]

In my case, the inverter bank is totally separate from the stater batteries. Each engine has 2 8D's, run in series to provide 24v. The bow thruster has another 2 8D's and the generator also has a dedicated group 27.

Paul

 

[kaz911]

Interesting that I'm hearing a few folks recommending Trojan batteries (on this and the earlier thread). One of the other questions I had is, what brand should I choose? I was also looking at Surette/Rolls, which makes a good marine product. Any others with good experiences with a particular battery manufacturer?

Paul

My toplist is Rolls and Lifeline (Concorde). Optima Bluetops are in at the moment - but they are just > 1 year - and already showing sign of capacity loss. It seems they don't like the very hot weather where I am.

 

[Dave M.]

I have had good luck with Exide golf cart batteries. I have four of them, but sometimes two of them are in the 5th wheel, as they are right now. I need to move them back to the boat to restore balance, I have a list now. Mine are connected to a Heart Interface 2KW inverter/100amp charger. I just bought and installed a Victron battery monitor in the boat to check on things electrical. Anyway, my batteries were manufactured in 2004, so are now 9 years old. I did a load test on one pair two months ago. I drew out 160 amp-hrs, and decided to stop. I needed to derate for low temp, and thought I should derate at least 10% for age. Since they are a 200 amp-hr battery, I decided they were good enough and no sense taking them all the way down. They have served me well.

Nine years is about the same lifetime I have seen with commercial VRLA batteries, guaranteed for 20 years, in a telco setting where 20 years is the norm. Unlike those, mine are still going, but they are nearing end of life, as they are exhibiting positive plate growth.

 

[Jackie J V]

UPDATE TIME:

After much research and discussion, I decided to go with a bank of 8 x L-16 batteries and upgrade the inverter. I'm going to go with Interstate batteries. Why?

Why the L-16's?

Essentially it comes down to maximizing available space. Height isn't a restriction for me so the L-16's provided me more amp hours for the same floor space than golf cart batteries. Otherwise, I would have gone for the golf cart batteries as they're a very proven a reliable choice for deep discharge applications. L-16's are also a decent choice. While originally designed for industrial floor scrubbers, they are often now used in off-grid solar or wind power applications.

I also looked at a custom industrial battery solution which essentially is bunch of 2V cells bundled together in a steel case. This also would be a good solution, however I was concerned with size (steel case with opening lid was starting to become an issue with height) and support (not a solution from my marina and wouldn't be something that I could replace in a jiffy - which would be a problem if the bank died mid season).

Eight L-16's will give me 1680 amp hours (12V) at the 20hr rate.

Weight was also a significant consideration as the boat is already a little aft-heavy, especially with the dingy mounted on the swim platform. Given that these new batteries would total 950lbs (up from 600lbs previously), after considering a number of alternatives, I also decided to relocate the batteries to midship from where the 8D's were located in the lazarette. I had custom battery boxes made to house the batteries in the walkway between the engines. Here's a pic I took yesterday of the solution in process:

It's really not as tight as it looks in the pic. There's plenty of space to walk through and I don't think it'll interfere with access to any part of the engines as the boxes are roughly the same height as the stringers. Plus as a bonus, it provides me a place to sit with a beer as I'm spending some quality time with the Cats...

Why Interstate?

I was also looking for recommendations on battery suppliers and I thank those who gave recommendations. Personal opinion - I believe another battery manufacturer such as Trojan or Rolls/Surrette would be a better product and I came close to going Rolls/Surrette, however those suckers had about a six week ordering time. Again, if batteries died mid season, I wanted to have a solution that could be replaced quickly. The Interstates are also a lot less expensive (about 70% less) and are sold and supported by my marina (again an important consideration for me).

Why upgrade the inverter?

Essentially this was more about the charging capability than the inverter capacity. With the much larger battery bank (about 85% larger than previous) I wanted to be able to recharge without running the generator all the time (which would kinda defeat the purpose). I could have gone about this a number of ways (added charger, bolted on another Victron MultiPlus 3KVA), however I wanted to keep things as clean as possible. Consequently, I upgraded to a Victron 24/5000/120 Quattro. This gives me 120 Amps at 24V which is double the 120A at 12V that I had before, which essentially cuts the charging time in half. I could have gone for a less expensive inverter, however I had a lot of success with the previous inverter and like the Victron product.

Hopefully this is helpful at somepoint to someone facing the same conundrum...

Cheers!
Paul

 

[HUMPH]

Nice setup Paul. I would be a bit concerned in narrowing your walkway but it seems you have taken this into consideration. The access in the engine room is one (one) of the things I love about the 560DB. The weight distribution does make sense though.