Charging 4 Battery Banks

[keaislandsailor]

I've been reading posts and watching recommended videos, but still have some questions.


I want to charge 3 AGM banks and 1 Lithium bank as follows:

1. Motor battery for 2019 Yanmar 4JH80.

2. Gen Battery for 2019 Northern lights M673L3.

3. Windlass Batteries (2)

4. House bank (lithium)

With Five Potential Power supplies:

1. One Solar Panel system for AGM.

2. One Solar Panel System for Lithium

3. Motor Alternator

4. Generator Alternator

5. Battery Charger

Questions:

a) Is one AGM start battery sufficient for Motor and Generator?

b) If the Alternator(s) goes to each bank, is there a device that goes between alternator and banks that regulates the charge for the AGM banks and lithium bank? Or, do the MPPT Solar Controllers perform this task? Would you use the Alternator(s) for the Lithium bank or is it too risky?

c) Would you use both the Motor and Generator alternator on the AGM banks, too, or just the Motor Alternator?

e) Anyone know a good electrician that services the downtown St. Petersburg, FL municipal marina?

Thanks, everyone.

[ranger58sb]

Can't speak to lithium but...

AGMs don't self-discharge very much. It could be reasonable to charge the engine start battery only with the engine alternator, and the generator start battery with the generator alternator. Might be possible to extend that reasoning to the windlass batteries, too... using the propulsion engine alternator.

An AGM battery that will start your propulsion engine is sufficient to start your generator. I would prefer instead to have two separate batteries for those functions, and at least a set of jumper cables (assuming a diesel boat).

FWIW, our genset AGM start battery is only charged by the generator's alternator. Been that way for 10 years or so I think, no issues so far. We only use a battery charger on the house banks.

-Chris

[tkeithlu]

Ours:
Engine start battery charged by simple alternator on engine
Genset start battery charged by simple alternator on main genset
House bank charged by Balmar alternator on main engine
House bank charged by battery charger from shore power or main genset
"Shore power" can be pull-start small genset

But, jumper cables allow crossing:
Parallel engine and genset start batteries (saved us when engine start battery died)
Start engine or genset with house batteries (also been used)

The point here is to be able to get a source of charge going when the usual way fails. It's not much good to have full house batteries if you can't start the engine or genset. You never know for sure that you are not going to wake up to a dead battery.

If we woke up with all batteries dead and away from shore power (hard to imagine) the sequence would be Start small genset by hand, use that to run the battery charger, divert power to starting the engine or the main genset, and we recover our reserve.

[svspirited]

It is fine to have a single AGM for the genny and main, it's how mine is set up and it works fine. I have no lithium but my current setup is AGM for the starter battery and gel for the house bank, it will be switched to Lithium once the gels finally die but so far they are 7 years old and holding up well. I have a battery combiner so I can pull from the house bank should the starter battery die, something that came in very handy recently. The starter battery is charged by the engine alternator and can be charged through the solar array when switching the battery combiner on, generally I don't find it necessary since the main/genny typically run long enough to replace whatever charge was used up in starting them.


The house bank is 600ah group 31 gels that are 7 years old and still running strong, the 600 watts of solar and the wind generator keep them topped up and we rarely run the batteries below 80% and that only happens when sailing in cloudy or nighttime conditions. When at anchor we rarely drop below 88% and that is with a seafrost fridge and separate seafrost freezer keeping the beer cold and the ice made.

[a64pilot]

I don’t understand the desire or need for so many battery banks.
I have one, why would I want several? I have only only one fuel tank too, and a battery bank is pretty much an electrical equal.
I do have a Honda though and like above I can start it and charge enough to get the generator going and charge the rest of the bank, or just charge with the Honda, or Solar.
Now I may only have one bank, but I have several charge sources, I like redundancy there.

So the bank dies, actually mine is right now as we speak, but if an individual battery were to die then I remove it or a pair actually as mine are 6V.

Having multiple banks in my opinion only really increase the likelihood of a bank failure.

So your going Lithium, why do you want a Windlass bank?

Then two solar panels? One for Lithium and one for AGM?
No especially if you only have two put them both on the house bank, they won’t be enough as it is and one certainly isnt

[moseriw]

a.) Yes, though reduced to 3 Banks. Battery sxhould be > 75 Ah for starters only
b.) no, yes (one could write a dissertation about the damned IOIO something), yes - but...
c.) did not knowv that the genset has an alternator!! Usually it transfers to 110 or 230V
d.) ??
e) Anyone know a good electrician that services the downtown St. Petersburg, FL municipal marina?

Should be a very very good electrician and worth flying him in!!

----------------------------------
Nearly everyone who takes it serious has the same f...ing problems with the different chargers.

What I am going to do is with AGM and FLA (for Lithium In would think about a Battery to battery Charger) is :
going to buy a cheap 200A 110-230VAC to 14,4 or 14,8VDC for Shore and Genpower
That is around 500 USD
Then connect it to an 200A Alternator to Battery Charger with 2 Ports
1x Engine Battery
1x else
Next 500 USD
On else connect an 200A ArgoFET Battery isolator with 3 Ports (150 USD)
INPUT = A2B, MPPT, Windgenerator....
Output1 House (if possible)
Output2 Bow
Output2 Spare
---------------------------------
OK I have AGM and FLA and should be on the safe side but I think this is a cheap
and clean solution without hell of a mess of chargers around

[sailcrazy]

Designed and built our setup about 16 years ago...and it's still working fine. Since eng starter loads are different than house loads, we used a single, conventional, sealed NoMx battery to start both the main eng and the genset; it's recharged by the genset alternator and a Balmar Duo-Charge from the house bank. Ea pair in the house bank (6- T-105s) go to an ON/Off sw, then a common busbar. The eng alternator feeds that busbar, as does the solar controller and the windgen controller. Each pair of T-105s has a separate feed from the batt charger. I can disconnect/remove any single or pair of batts, should one fail/short out, but they all 6 are normally online. The start batt gets recharged from the house (Duo-Charge). The bilge pumps+alarms and the windlass come directly off the busbar, and the house loads are fed via a main disc sw, a whole-house fuse, and the dist panel. And I have a parallel sw between the house and start batts. So far, since 2003, never have run out of power, and batts seem to last about 7 years.

[vpbarkley]

These posts help me come to terms with my recently purchased boat's electrical system.
2 FLA batteries, 1 at engine, 1 at bow thruster/windlass, both charged by engine.
1 FLA battery for and charged by genset.
12 AGM battery bank. Charger for shore power or genset. MPPTs for solar and wind.
There's lots of redundant capability here but this seems crazy complicated.

[MJH]

Originally Posted by keaislandsailor

I've been reading posts and watching recommended videos, but still have some questions.


I want to charge 3 AGM banks and 1 Lithium bank as follows:

1. Motor battery for 2019 Yanmar 4JH80.

2. Gen Battery for 2019 Northern lights M673L3.

3. Windlass Batteries (2)

4. House bank (lithium)

With Five Potential Power supplies:

1. One Solar Panel system for AGM.

2. One Solar Panel System for Lithium

3. Motor Alternator

4. Generator Alternator

5. Battery Charger

Questions:

a) Is one AGM start battery sufficient for Motor and Generator?

b) If the Alternator(s) goes to each bank, is there a device that goes between alternator and banks that regulates the charge for the AGM banks and lithium bank? Or, do the MPPT Solar Controllers perform this task? Would you use the Alternator(s) for the Lithium bank or is it too risky?

c) Would you use both the Motor and Generator alternator on the AGM banks, too, or just the Motor Alternator?

e) Anyone know a good electrician that services the downtown St. Petersburg, FL municipal marina?

Thanks, everyone.

Are you talking four batteries or four banks? A bank can have more than one battery in it. You are making it more complicated than it needs to be.

I have two banks: one for Start and one for the House. The start battery is one group 27 battery bank, the house is 2x8D batteries...all are Gel batteries which eliminates any cross chemistry problems...my previous house Gel batteries lasted 15 years.

My 4x140W solar panels are connected directly to the 2x8D Gels via controllers, one controller for two panels connected to one 8D. The Start battery bank does that and nothing else...I don't have a genset but would connect it to it if I did.

The House bank of 2x8D Gels powers every thing else including the windlass.

The alternator is a Balmar 110A with Balmar MC-614-H regulator.

The Statpower True Charge 40+ charger is set to charge Gel batteries only...there is no option for multiple battery chemistries.

Lastly, I have a Blue Sea Systems Automatic Charging Relay (ACR) between the start and house banks to insure the start bank is always charged.

I don't like mixing battery chemistries. Simplify by combining batteries into just two banks of all the same chemistry.

Good Luck,

~ ~ _/) ~ ~ MJH

[KP44]

Originally Posted by keaislandsailor

I want to charge 3 AGM banks and 1 Lithium bank as follows:

1. Motor battery for 2019 Yanmar 4JH80.

2. Gen Battery for 2019 Northern lights M673L3.

3. Windlass Batteries (2)

4. House bank (lithium)

With Five Potential Power supplies:

1. One Solar Panel system for AGM.

2. One Solar Panel System for Lithium

3. Motor Alternator

4. Generator Alternator

5. Battery Charger


Thanks, everyone.

It is important to separate your engine battery, What you call your motor battery. It should be separate from your house bank. That is because you always want to be able to start your engine, even if you have accidently left something on and your house bank is dead.

All other systems, including windlass, should be on the single house bank. Take the money you save by keeping this simple and buy extra lithium battery(s) for your house bank.

Put all your solar, your shorepower charger, and your engine alternator to your house bank. (Get the proper controllers for your lithium batteries.)

Your shorepower charger probably has an option to charge a separate engine battery, so use that. Your engine alternator system can be configured with an isolator so it can charge your engine battery as well as your house bank.

Your gen-set will run your shorepower charger, so that simplifies that.

We usually start the engine when we are using the windlass. Thus, the alternator is supplying power and there is no drain on the batteries.

Keep it simple. One house bank and one battery (or bank) dedicated to starting the engine.

[CassidyNZ]

I have two banks, seems most common and logical. But mine are viewed/named differently.

I have a house bank (800ah) that does everything including starting the engine. This is what is used all the time for all electrical needs. I have two alternators driven by the engine each with switchable fields so I can turn them on and off as required. I have 800W of solar and a small wind gen input and all of these charge sources go directly to this bank but can be linked to the emergency bank via a 1-All-2 switch.

Then I have an emergency bank that is used to start the engine when the house bank is inadequate. This second bank includes a battery in the engine room and another in the anchor chain locker (runs the anchor winch). I have the standard engine alternator dedicated to charging this bank so whenever the engine runs, this bank gets charged (60A). When the anchor winch runs this bank provides the power and the anchor winch only runs when the engine is running. Other than that it is just that, an emergency bank.

I have never discovered a reason for this system to be more complicated. I have no “automatic” load sharing, charge sharing devices. I run my electrics almost as a hobby, monitoring draw and charge, switching things on and off manually to ensure constantly healthy energy resources. So far in 40 years of owning cruising boats it has never let me down.

[Starblossom]

I suggest you look into the Sterling alternator to battery charger. It will simplify your life

[dougweibel]

Originally Posted by a64pilot

I don’t understand the desire or need for so many battery banks.

One reason for multiple banks, not that this necessarily applies to the OP, is the location of the loads. If your house bank is aft you can either run big cables all the way forward for the windlass, and perhaps a bow thruster, or much smaller cables to a battery located near the windlass. With an automatic charge relay in the circuit you then have a backup battery to get the engine started if the house bank is dead.

[a64pilot]

Originally Posted by dougweibel

One reason for multiple banks, not that this necessarily applies to the OP, is the location of the loads. If your house bank is aft you can either run big cables all the way forward for the windlass, and perhaps a bow thruster, or much smaller cables to a battery located near the windlass. With an automatic charge relay in the circuit you then have a backup battery to get the engine started if the house bank is dead.

Understood, but unless you have a rather large boat it’s just not necessary to be putting batteries near the load, just as you say run larger cables, larger cables last forever and are very simple, ACR’s and multiple banks are not. Plus the obvious fact that your carrying around a lot of dead lead, weight that does nothing except when it’s time to raise the anchor, otherwise it’s wasted weight and money.
OK as he’s going Lithium I can see the desire to have a separate old fashioned starter battery, but surely any Lithium bank is capable of operating bow thrusters and windlasses.

You can make this as complex as you want to, or you can keep it simple.
Accidentally leaving something on and waking up to a dead bank, really?
How do you do that? If you really think that’s possible then have a low voltage alarm, my amp meter has one built in.

I don’t know how people can run around in single engine boats with one fuel tank and think that they need multiple battery banks for safety, cause one could go dead and they not know it.
But for some reason they have no concern about running out of fuel and not knowing it.

[moseriw]

Understood, but unless you have a rather large boat it’s just not necessary to be putting batteries near the load, just as you say run larger cables, larger cables last forever and are very simple.

OK Facts:
Battery 12V 225Ah FLA
Bowtruster 6Kw = 500A
Windlass 1,6 Kw = 110A

cable 95 mm² length 12m
input Voltage (12,6V battery) and 14,4V from alternator

Windlass draws 100A
Voltage drops from 14,4 to 8,9V

Which cables should I use? 300mm² ??
And this ruins your windlass and bowthruster motors within hours of service!

I think one should learn from my faults!!

I consider a bow-battery as an ultimative MUST HAVE!

And for the NON BELIEVERS: don't discuss - check for yourself on your boat.
One should to get at least 11V (on emergency) even if the battery is down to 11,8V aka empty.