Faster battery charging on the hook

[Swfla]

And the redundancy is nice, I have at least 25a at 120v free on the B side of my panel (non inverted side) so could fit a pretty big charger.
That said I can’t seem to find a large marine charger above 160a.

Have you looked at RV, residential or commercial(off grid) chargers? They may offer greater capacity. It's possible that a vessel of your quality and build may have plenty of protection from a "salty" environment. Being in PNW, a lot of time is spent in fresh water. Cheers
Edit: I spent 20 minutes googling on your behalf. Duo Regen makes forklift battery chargers with very high capacities. I imagine there are other companies as well. Worth a look?

 

[Arthurc]

Really good advice all, thanks!

OC, good call out on the need to really think about the bank and wiring, it’s all 4/0 wires and lifeline l16 agms less than two years old, runs are very short and well fused.

Rslifkin,
Loads are just a lot of stuff, between redundant internet connections, leaving much of the electronics on 24x7, Apple TV’s and other electronics, hydronic heating, a camera system, 2 fridges and a freezer, dishwasher, etc it’s hard to plan. I do plan around the washer/dryer but more because it’s on the Non inverted side.


For now I think I’ll look into solar, if I can step on them I can cover my PH roof without issue.

I tested with the 40a portable charger and it worked well, might also install a 60-100a standalone charger and call it good, even with the main running that would be a max of 450a into the batteries and I can call lifeline to make sure that’s ok.

AC

 

[rslifkin]

How much of the PH roof do you actually need to walk on? If it's just to get to 1 or 2 things, you can probably place the panels to leave a walkway and just sacrifice a little bit of solar capacity. I don't know of any solar panels that would be happy with getting walked on.

 

[dhays]

If I'm not mistaken, Lifeline batteries can take a pretty high bulk charge, as much as 5 times the Ah capacity of the bank. So in my mind, your charging rate is just way too low. I'd look at the above options for increasing your charge rate up to the load that your generator could handle. No way to rush the absorption or float stage however.


It sounds like you don't want to be limited in your power consumption, so I think you may simply resign yourself to running your generator close to to 24/7. Many folks with larger AC boats do just that.

 

[Arthurc]

How much of the PH roof do you actually need to walk on? If it's just to get to 1 or 2 things, you can probably place the panels to leave a walkway and just sacrifice a little bit of solar capacity. I don't know of any solar panels that would be happy with getting walked on.

Unfortunately a good chunk of it since the boom connections are there.

 

[Russell Clifton]

When I bought our current boat a stand alone battery charger had been installed. I never could figure how I would use it so just let it sit for the past four years. This year I decided to find out if it would help the inverter charge the batteries faster. It did not work. Just sat there on standby and put out no amps. (It will charge the batteries when the inverter is off.) I am thinking that because the inverter was already pumping out over 100 amps the stand alone charger did not sense it needed to connect? Or maybe it is the way it is wired up?

 

[Airstream345]

Arthur, I’m beginning to think our project lists are converging!

We just installed Firefly batteries primarily for their resilience (they don’t need to get to float more than once in a while) and their ability to deeply discharge in an effort to get more “practical” usable Ah on the hook. They also can take up to .4C charge which means our 696Ah bank can accept a 278 amp charge.

Immediately we realized our Magnum 2012 can’t come close to that so we’re running for four hours in the morning and three go four before bed. We time this with laundry, RO, showers, coffee maker time, etc but its still lot of genny time.

A dock neighbor just installed the Victron Quattro and there is a lot to like, especially if you’re adding solar later (which we are).

200A charge, dual AC input with auto switching with protection for electronics, auto generator start capable, stackable, 5000W pure sine wave output. Victron also has some pretty sweet monitoring and integration capability.

I plan to install in the Fall.

 

[Arthurc]

Let me know how it goes, First night on the hook in a long time and I realized I want an inverter on the B side too, batteries got to float, went to turn off the gen and she had just started laundry... 3 hours later I finally got the gen off...

 

[Ventana]

We designed an electrical system for a boat when lithium battery technology was still in it’s infancy in the marine market, with the goal of multiple charging sources each capable of more than 300A output to take advantage of the lithiums high charge acceptance. We ended up using mostly Victron equipment, as they were willing to work with us ironing out the little details. We also included a Fischer Panda DC generator that maxed out at just under 400A. The biggest issue when you get into this amperage range is cable sizing and connections to keep heat buildup under control, and heat dissipation from the various charge sources. Your ideas and the advice you are getting is very doable, just make sure you think through the details.

 

[stevemitchell]

I updated my DC/AC electrical system last year (https://seabits.com/victron-wakespeed-battle-born-power-system/) and replaced a Magnum inverter/charger with a Victron MultiPlus 3000W inverter/charger and added LiFePO4 batteries. The inverter/charger charges the house bank at 120 amps, but that wasn't enough while at anchor.

I added an additional 60 amp charger that runs only while the generator is on for a total of 180 amps of charging. It is setup with the same profile as the Victron inverter/charger so things are all happy. I would have liked to add more, but my other loads (water heater, water maker, etc.) usually brings the generator right up to near the limit, keeping it fully loaded as much as possible.

It cuts down on the charging time while at anchor. Charging while underway is much faster as I have around 320 amps of capacity there from the alternators. Add in the generator, and it makes it even faster...

 

[FF]

Roll your own noisemaker / charger , you can do better than the current crop of 60 year old designs.

A DN 50,alternator can be had in 12 or 24v up to 450a at 24v.

There expensive new but dirt cheap rebuilt since they have been building them for 30-40 years.

A Kubota or other diesel could be selected to operate the unit at just the speed required to keep up the voltage for rapid DC charge.

A large inverter could power the house goodies while charging .

The variable speed would allow the diesel to be very quiet and more efficient when operated slowly .

50DN™ High Output Heavy Duty Brushless Alternator | Delco ...

www.delcoremy.com › find-by-model-family › 50dn

The 50DN is designed for transit bus and motor coach applications. Providing 270 amps at 24 volts the 50DN provides plenty of power at low engine speeds.

 

[ranger58sb]

Interesting idea, I like it, and frankly it’s not that much more, biggest consideration is mounting location. I do want to ditch my xantrex for a magnum so I could use the xantrex as the backup. Only issue is won’t they be out of sync and affect my 240v stuff (CruisAir)

You're running your ACs on inverted AC? (so to speak)

Water heater too?

-Chris

 

[DDW]

Lifeline batteries can be charged at bulk/absorb voltage without current limit. Practically they will not take more than about .5C for very long as the chemistry limits it. You might see 1 or 2C for a short period if really discharged. In your case that means 800 amps. Your DC system really cries out to be converted to 24V which would reduce the amp by half and the wire sizes needed. But that is a big change.

 

[Arthurc]

You're running your ACs on inverted AC? (so to speak)

Water heater too?

-Chris

Right now all outlets plus hydronic heating, dishwasher and all kitchen stuff are inverted. Non-inverted is my hot water heater, washer/dryer, watermaker and the CruisAir units. I don’t care much about hot water as I’ve got engine and hydronic loops plus an instahot system of the boiler is running.
Biggest reason to invert the other side is the washer/dryer and watermaker while underway. I’d leave the CruisAirs, hot water heater and fridge AC on gen/shore only. So far the raritan 20g stays hot easily for 12+ hours so no need assuming I’m doing something to charge daily.

 

[Xsbank]

I think your solution is a much quieter muffler for your genset.

 

[Arthurc]

Already there, can’t hear it actually unless I really try, the ice maker in the galley is far more irritating.
I’m more trying to figure out how I don’t run it for so many hours at low load. I have two 30a outlets up top for family who raft up but that’s rare and unless it’s freezing and I’m running the cruisairs full blast (problem solved this year with the hydronic heating) I’ve never come close to fully loading the gen.

 

[FF]

"I’m more trying to figure out how I don’t run it for so many hours at low load."

If the "low load" is getting the house batts from 85% to 100% , the simplest is to over size the house batts and not bother.

Sure the batts will slowly degrade but you can still pull the needed amps out .

 

[Sleeping Bear]

Charging

I am running a smaller system, but instead of jumping through all the hoops, I realized my genset has an alternator to charge its starter battery.

As it only takes seconds to recharge the genset battery after start, I hooked an automatic charging relay betwen the house and the genset battery, so for the bulk charging period the genset is putting power from both ends as it were, reduces the bulk charge time, the absorption period is done with solar.

The ACR works both ways, so keeps the genset battery at max when the house is charged, which keeps the time the genset takes to charge its battery to a minimum before it switches to house.

So maybe a larger alternator on your genset and an ACR?

 

[Arthurc]

That’s a super interesting idea, my Balmar makes quick work of my house bank on the main, will need to see what size if any alternator is on the 12kw NL and what would fit in the enclosure.

 

[DDW]

"I’m more trying to figure out how I don’t run it for so many hours at low load."

If the "low load" is getting the house batts from 85% to 100% , the simplest is to over size the house batts and not bother.

Sure the batts will slowly degrade but you can still pull the needed amps out .

If you never (or infrequently) charge your AGM batteries above 85%, the degradation will be rapid. Change to flooded batteries if you are going to do that.

 

[ksanders]

I think your solution is a much quieter muffler for your genset.

Actually his solution is to add a 2nd inverter/charger doubling his charging capacity.

His Xantrex charger is already capable of doing this as the two inverter/chargers can communicate with each other via the System Control Panel.

This is a manufacturer supported solution.

 

[OldDan1943]

A. larger alternator on the main engine
B. larger AC charger in conjunction with generator.
C. tack on solar panels to finish the battery charge and float the batteries.

Per inverters.... unless your boat is designed to be totally supported via an inverter, I think the change over to a total inverter boat would be expensive. You need lots of battery power aka more batteries than you might have now.
I think inverters suck out more battery power than can immediately put back in or float. Use wisely, watch the DC and AC voltage meters. Engine electronics are not designed to run on low battery voltage (shut down about 10.6 volts.) I suspect microwave are not designed to run on low battery voltage via inverter,either.

Yes, I have added a 3rd 4D house battery, a couple of solar panels. I have a standard 40amp battery charger and a standard alternator on the Cummins, I think 180 amp output but would need to locate my spare alternator to make sure.

My goat is to keep this boat as stock as possible, in consideration for the next owner.

 

[BobMc]

When we upgraded from Xantrex/whatever to Magnum 2812 we left the Xantrex/whatever in place. When at anchor for more than 2-3 days and need to recharge the batteries we can use both combined to get 225 amp charge when running the genset. Doesn't take long to add about 15% to the 1100 amp battery bank at that rate! At least we don't have to run the genset for 4 hours simply to charge batteries. We have propane stove, so never run the genset except in dire extremes when we need AC or need to charge the batteries. Everything else runs off the Magnum inverter.

Has anyone figured out a slick solution for faster battery charging while off shore power?

AC

 

[Poach]

Batt charging time

Has anyone figured out a slick solution for faster battery charging while off shore power?

Someone probably mentions this, but on a Magnum, you can adjust the amount of power your inverter/charger is sending to the batts.

 

[Captain James]

Yes but you are upside down downunder.
For you the sun comes right out of the ground.

 

[IslandTractor]

An alternative strategy would be to replace your AGM battery Bank with a lithium bank. A lithium battery bank could be considerably smaller as it can be safely discharged much deeper than 50% SOC and will accept full generator/charger output until 100% SOC rather than wasting time in acceptance or float stage. Obviously this isn’t a cheap solution but Battleborn lithium batteries go for about $1000 per 100 amp/hr and a rough guess would suggest that nine or ten of them would replace your 1600 amp/hr AGM bank.

 

[OldDan1943]

Obviously this isn’t a cheap solution but Battleborn lithium batteries go for about $1000 per 100 amp/hr and a rough guess would suggest that nine or ten of them would replace your 1600 amp/hr AGM bank.

$1000/100amps?
I can buy a lot of AGM batteries for that.

 

[dhays]

$1000/100amps?
I can buy a lot of AGM batteries for that.

Can buy a lot of fuel for a generator as well....

 

[IslandTractor]

$1000/100amps?
I can buy a lot of AGM batteries for that.

Yep you sure can and you can spend lots more time recharging each day too. Point of the OP was to reduce charging time on the hook.

 

[w8n4sun]

Arthur, I'm seriously contemplating upgrading from FLA to Lithium and a large requirement is reducing generator run time to a very minimum. I'd love to hear if you decide to head down this path? Thanks and good luck.