Once Again - LIthium Battery Install?

P

Pat Anderson

New member
Here is what I THINK my lithium battery install might look like.

k_Diagram_of_Lithium_Battery_Charging_System.sized.jpg

I know I need the lithium battery and a DC to DC charger., but not what else I might need. I want to use three charging sources: the Suzuki alternator through the Voltage Sensing Relay so it can charge both the FLA starting battery and the lithium battery, the solar controller (200 watts of solar on roof and an MPPT controller that has a lithium setting), and shore power.

The VSR, for those who don't have one, charges the starting battery first until it sense that it is fully charged, and automatically switches charging over to the house battery side. I know that would have to go through the DC to DC charger. The Suzuki DF200 has plenty of amps for that.

The solar can just go directly to the lithium battery with the controller set to lithium.

It is the last part (shore power) that is puzzling me. Do I need to replace the Guest 10-10? Can I just have it charge the FLA starting battery and run from that into to the DC to DC charger? Can I hook both the house side of the Voltage Sensing Relay and the starting battery to the DC to DC charger? Should I remove the cable from the starting battery so charging only happens when the engine is running or the sun is shining? Or something entirely different?

Help would be greatly appreciated from those who know whereof they speak!
 
It is the last part (shore power) that is puzzling me. Do I need to replace the Guest 10-10? Can I just have it charge the FLA starting battery and run from that into to the DC to DC charger?
Click to expand...

You will be limited to the 10 amps which the mains battery charger can put out. It will be fairly slow charging the LI battery. As long as the Guest charger is working well, no real reason to change, unless you want a better charger which is a "smart charger. The smart charger will sample the starting battery voltage, and give as much current as the FLA starting battery will take. One of the features of the LI battery is to charge it rapidly. (For example I used an 80 amp charger on my setup, and could have easily used a 100 or 120 amp charger. If you want to charge the battery from a low state of charge in a short time, then you do not have the advantage of the battery being able to take this increased charge.


Take one of the jump start packs (like the WeGo), because you no longer have the ability to use the house bank to start your engine, if for some reason the starting battery went bad.


The VSR, for those who don't have one, charges the starting battery first until it sense that it is fully charged, and automatically switches charging over to the house battery side. I know that would have to go through the DC to DC charger. The Suzuki DF200 has plenty of amps for that.
Click to expand...

The first part is not technically correct. The VSR combines two batteries when the voltage reaches a set voltage--often 13.7 volts. This in no way implies that the start battery is fully charged. The VSR is just a dumb relay, which acts to close when a set voltage is reached, or below a set voltage, to avoid pulling power off the engine start battery and running it down.

The DC to DC charger acts just like the VSR. You do not really need the VSR and I believe it complicates your system. If you had an AGM or FLA house battery, then it would be connected between the FLA house and the start battery.
 
Par, the VSR as you describe it is wrong, take it out. How about that for a simple statement?

So, now let me say this about that. The VSR will charge the start FLA battery from the Suzuk and when that battery reaches some level, change over to the house battery. Now, what happens when the house battery reaches full charge? The DC-DC charger and BMS ( I hope the battery has one) opens up and the Suzuk alternator current has nowhere to go and fries.

So, take the VSR out. And show the Li battery BMS even though it should be in the battery. This unit will both balance the Li cells and cut off the charge current.

Boris[/img]
 
thataway":3w243bbk said:
You will be limited to the 10 amps which the mains battery charger can put out. It will be fairly slow charging the LI battery. As long as the Guest charger is working well, no real reason to change, unless you want a better charger which is a "smart charger. The smart charger will sample the starting battery voltage, and give as much current as the FLA starting battery will take. One of the features of the LI battery is to charge it rapidly. (For example I used an 80 amp charger on my setup, and could have easily used a 100 or 120 amp charger. If you want to charge the battery from a low state of charge in a short time, then you do not have the advantage of the battery being able to take this increased charge.
Click to expand...

Thanks, Bob. How would what you are saying change my block diagram? Can both the alternator and the Guest both go into input of the DC to DC charge (my main question)? Sounds like changing out the Guest would be a good idea, but to start I probably will just just keep the Guest. I think I don't care how fast the battery gets charged in my driveway - or do I?

thataway":3w243bbk said:
Take one of the jump start packs (like the WeGo), because you no longer have the ability to use the house bank to start your engine, if for some reason the starting battery went bad.
Click to expand...
.
Got it, will do

thataway":3w243bbk said:
first part is not technically correct. The VSR combines two batteries when the voltage reaches a set voltage--often 13.7 volts. This in no way implies that the start battery is fully charged. The VSR is just a dumb relay, which acts to close when a set voltage is reached, or below a set voltage, to avoid pulling power off the engine start battery and running it down.

The DC to DC charger acts just like the VSR. You do not really need the VSR and I believe it complicates your system. If you had an AGM or FLA house battery, then it would be connected between the FLA house and the start battery.
Click to expand...

Yes, the alternator is connected to the VSR, and the VSR is currrently connected to the starting battery on one side and the FLA bank on the other. So I sort of assumed when the starting battery reaches 13.7 volts it would indicate it was sufficiently charged. Then output would continue to the FLA starting battery on one side and to the DC to DC charger going to the lithium battery on the other. If the DC to DC charger acts like the VSR, how do I need to change my diagram? Just connect the alternator directly to the DC to DC charger? How does the DC to DC charger loop back to then charge the starting battery if not through the VSR?

I don't mean to be obtuse but I need to have a clear understanding so I don't blow anything up!
 
journey on":ilofl4dr said:
Pat, the VSR as you describe it is wrong, take it out. How about that for a simple statement?

So, now let me say this about that. The VSR will charge the start FLA battery from the Suzuki and when that battery reaches some level, change over to the house battery. Now, what happens when the house battery reaches full charge? The DC-DC charger and BMS ( I hope the battery has one) opens up and the Suzuki alternator current has nowhere to go and fries.

So, take the VSR out. And show the Li battery BMS even though it should be in the battery. This unit will both balance the Li cells and cut off the charge current.

Boris[/img]
Click to expand...

Thanks, Boris, I certainly don't want to fry anything! That is why I posted my questions here first!

Here is the battery I am looking at - it has a BMS and bluetooth - and it just went up by $20 overnight. Same questions for you as for Bob. How does my diagram change, i.e. what gets connected to what, and how does the starting battery get charged? Does the alternator go directly to both the starting battery and the DC to DC converter? Can you print my diagram and make changes to it with a Sharpie and either scan and post here or mail it back to me if I PM you my address?
 
The Suzuki engine "cable". goes directly to the FLA Positive and Negative terminals. (There will be the engine cable and one other cable to a bus bar or single terminal point near the FLA battery. The second cable to the FLA start battery will be directly to the Positive terminal of the FLA start battery.

No VSR.

The DC to DC charger goes directly to the start FLA Start battery bus bar terminals or stud, via a 40 amp breaker. This can also act as an "On/Off switch for the DC to DC charger". There may be times you don't want the start battery connected to the DC to DC charger. (Like when there is no charging of the FLA start battery, by engine, or the mains power battery charger.)

The Guest 10 amp charger goes directly to the FLA start battery bus bar terminals. (fused on both ends)

We have not "talked" about fusing or breakers. The DC to DC charger should have a 40 amp fuse or breaker at the output of the wire going to the Li battery. If the lead to that battery is more than a few feet, there should be another fuse/breaker at the end near the Li battery. (For example, in my 25, the Li batteries were under the bunk, so there was about 18 feet of wire between the DC to DC battery charger. In that case there as a 40 amp breaker at the output of the DC to DC battery charger and at the input of the Li battery.

I would put the mppt controller output to the input terminal of the Li battery. It would be fused (or breaker)

There will be a fuse / breaker from the li battery output to the house load. In my case, since I was running a 2000 Watt PSW inverter, I put a 300 amp fuse in place about 7" from the LiFePO4 battery. I put a 500 watt rated load battery switch between the Li Battery and the house load. (Be sure it is a good US brand like Blue Seas or BP.) If you are only running the normal "house load" then I would use a 60 amp breaker between the LI battery and the console or bus bar where you take the house load.

What battery do you run the windlass from? I used the start battery, thus used a 60 amp fuse to this circuit from the FLA Engine Start Battery bus bar. That needs to be near the busbar or terminal off the Start battery. You only want a couple of wires to positive terminal of the start battery. For neatness sake, put either a bus bar or at least a simple terminal for the cables to attach to the FLA engine start battery.
 
thataway":abgtvx9d said:
The Suzuki engine "cable". goes directly to the FLA Positive and Negative terminals. (There will be the engine cable and one other cable to a bus bar or single terminal point near the FLA battery. The second cable to the FLA start battery will be directly to the Positive terminal of the FLA start battery.

No VSR.

The DC to DC charger goes directly to the start FLA Start battery bus bar terminals or stud, via a 40 amp breaker. This can also act as an "On/Off switch for the DC to DC charger". There may be times you don't want the start battery connected to the DC to DC charger. (Like when there is no charging of the FLA start battery, by engine, or the mains power battery charger.)

The Guest 10 amp charger goes directly to the FLA start battery bus bar terminals. (fused on both ends)

We have not "talked" about fusing or breakers. The DC to DC charger should have a 40 amp fuse or breaker at the output of the wire going to the Li battery. If the lead to that battery is more than a few feet, there should be another fuse/breaker at the end near the Li battery. (For example, in my 25, the Li batteries were under the bunk, so there was about 18 feet of wire between the DC to DC battery charger. In that case there as a 40 amp breaker at the output of the DC to DC battery charger and at the input of the Li battery.

I would put the mppt controller output to the input terminal of the Li battery. It would be fused (or breaker)

There will be a fuse / breaker from the li battery output to the house load. In my case, since I was running a 2000 Watt PSW inverter, I put a 300 amp fuse in place about 7" from the LiFePO4 battery. I put a 500 watt rated load battery switch between the Li Battery and the house load. (Be sure it is a good US brand like Blue Seas or BP.) If you are only running the normal "house load" then I would use a 60 amp breaker between the LI battery and the console or bus bar where you take the house load.

What battery do you run the windlass from? I used the start battery, thus used a 60 amp fuse to this circuit from the FLA Engine Start Battery bus bar. That needs to be near the busbar or terminal off the Start battery. You only want a couple of wires to positive terminal of the start battery. For neatness sake, put either a bus bar or at least a simple terminal for the cables to attach to the FLA engine start battery.
Click to expand...

Thanks! Let me take the last question first! The windlass is powered from the starting battery, and we only use it when the engine is running. It was factory wired, as it was part of the 2005 factory Seattle Boat Show package. It has worked for the 17 years we have owned the boat. Not sure where the breaker for it is, but there is a large breaker right next to the starting battery. Up to now, I have not needed to get too deeply into what is what.

Your explanation seems clear enough. I will massage the diagram in the next few days and post the revised diagram! I obviously have a lot to learn about breakers and fuses!
 
Renogy 12V 100Ah Lithium Iron Phosphate Battery w/ Bluetooth and 12V 40A DC to DC On-Board Battery Charger ordered and confirmed!

On to LFS for required buss bars, breakers, and fuses!
 
And I should add that the total cost of the battery and DC to DC charger directly from Renogy was $683, or about the same amount as two AGM batteries - I know this because I just put two AGM batteries in my truck camper before I got tuned in to lithium batteries. Honey found a $36 coupon that came off the top and the purchase was tax free with free shipping. Of course there will be extra cost for buss bars, breakers and fuses, and I may end up upgrading the on-board Guest 10-10 shore power charger, but this makes sense for me. This battery will last longer and provide more usable power!

And with Dr. Bob's explicit directions, I have no doubt that I can do this myself. The hardest part I think will be lifting out the two EOL FLA batteries!
 
Pat, I'll certainly draw you my delta on your map. Please send me your original. The changes are minimal, get rid of the VSR and show the BMS.

The battery you've chosen @ $515 is a good battery and has heat, BMS and bluetooth; though what you'd use the latter for, I don't know.

Dr. Bob has covered the fusing, but I assume that fusing is already in place, please check. As both you and I have the same year boat with only a couple of months difference, I'd look and see if there's a breaker right back of the throttle, on the bulkhead. That's where mine is. I also seem to remember you replaced your windlass, as did I, for the later model. I also assume you kept the original wiring from the battery.

One additional comment is the use of buses and junctions. I used these for the small battery connections: Blue Seas Terminal Mount. For junction points (where 2 or more wires meet) I used these: Blue Seas posts. I assume you already have
larger bus bars.

I also used Marine cables, Even the tinned marine cables are cheaper than DIY, though one has to estimate the length when you order.


Boris
 
The diagram brings up a question I've had for awhile about adding a LiO battery dedicated to only my induction stovetop. If the VSR is eliminated, then the DC to DC charger goes only from the FLA battery to the LiO battery. I assume that the DC to DC charger is one-way, i.e., the LiO can't discharge back to the FLA.

Does a DC to DC charger have settings so that it can be configured specifically for this FLA/LiO setup? I ask because my understanding is that the LiO battery has a different preferred charge profile, generally faster and higher voltage. It seems like asking the lowly FLA, once at float, to then feed a starving LiO. Any issues with this? If not, why not?
 
Marco Flamingo":5emfp2u0 said:
The diagram brings up a question I've had for awhile about adding a LiO battery dedicated to only my induction stovetop. If the VSR is eliminated, then the DC to DC charger goes only from the FLA battery to the LiO battery. I assume that the DC to DC charger is one-way, i.e., the LiO can't discharge back to the FLA.

Does a DC to DC charger have settings so that it can be configured specifically for this FLA/LiO setup? I ask because my understanding is that the LiO battery has a different preferred charge profile, generally faster and higher voltage. It seems like asking the lowly FLA, once at float, to then feed a starving LiO. Any issues with this? If not, why not?
Click to expand...

If I have correctly understood Bob's post, ALL the normal charging sources (alternator, solar, and on-board Guest or other shore power charger) go directly to the FLA starting battery. The VSR is now out of the picture. The FLA starting battery is kind of a buffer for all charging sources. The FLA starting battery goes to the DC to DC charger input connectors. The DC to DC charger output connectors go to the LiO posts, and that charges the LiO battery. Your question about whether the FLS starting battery is up to the task, I do not know, but remember that afloat the LiO battery is mainly discharging power to the house, has lots of AHs to give, and will start recharging when you are running, the sun is shining, or you are connected to shore power. I will be doing a revised diagram based on Bob Austin's response and see if Bob and Boris approve. Ignore the diagram at the top, as Boris and Bob have both pointed out, it is simply wrong.
 
journey on":39hkcrzt said:
Pat, I'll certainly draw you my delta on your map. Please send me your original. The changes are minimal, get rid of the VSR and show the BMS.

The battery you've chosen @ $515 is a good battery and has heat, BMS and bluetooth; though what you'd use the latter for, I don't know.

Dr. Bob has covered the fusing, but I assume that fusing is already in place, please check. As both you and I have the same year boat with only a couple of months difference, I'd look and see if there's a breaker right back of the throttle, on the bulkhead. That's where mine is. I also seem to remember you replaced your windlass, as did I, for the later model. I also assume you kept the original wiring from the battery.

One additional comment is the use of buses and junctions. I used these for the small battery connections: Blue Seas Terminal Mount. For junction points (where 2 or more wires meet) I used these: Blue Seas posts. I assume you already have
larger bus bars.

I also used Marine cables, Even the tinned marine cables are cheaper than DIY, though one has to estimate the length when you order.


Boris
Click to expand...

Thanks, Boris - all great sources! No need to mark up my original diagram, I will be doing an entirely new one, and look forward to your and Bob's comments. What would the symbol for a BMS be?
 
To answer Mark's question: the DC to DC charger is "one way". I bought the Sterling (same as Pro mariner, Pro nautica. With this you can make any profile you want--but there is a specific LiFePO4 profile, as was as FLA and AGM.

The second question implied is that the Li battery may drain the FLA start battery. Because of this one can set limits on the DC to DC charger, and program so only works when the engine is running. This is one reason why I put a breaker or switch between the Li battery and FLA battery.

To give an example, I used the Li batteries to power our induction stove and the microwave, as well as refrigeration/freezer. I would charge the Li battery when we ran the outboard during the day thru DC to DC charger. Then I would switch off the DC charger, when I stopped the engine.
 
thataway":4x0c4rcq said:
To answer Mark's question: the DC to DC charger is "one way". I bought the Sterling (same as Pro mariner, Pro nautica. With this you can make any profile you want--but there is a specific LiFePO4 profile, as was as FLA and AGM.

The second question implied is that the Li battery may drain the FLA start battery. Because of this one can set limits on the DC to DC charger, and program so only works when the engine is running. This is one reason why I put a breaker or switch between the Li battery and FLA battery.

To give an example, I used the Li batteries to power our induction stove and the microwave, as well as refrigeration/freezer. I would charge the Li battery when we ran the outboard during the day thru DC to DC charger. Then I would switch off the DC charger, when I stopped the engine.
Click to expand...

You could put a relay connected to the engine side of the electrical system that only energizes the link between the Li and FLA batteries when the engine is running.
 
Let me repeat.

The Victron DC-DC charger has a motor running switch. This is to start the charger when the motor is running, by applying the motors 12 VDC output to the connection in the DC-DC charger. The DC-DC charger is disconnected at all other times, cannot backfeed, cannot charge.

This switch makes sure that the charger only works when the engine is running. NO RELAY NEEDED. Of course this does not allow charging when connected to shore power, so I've connected that switch to an external 12VDC source via a manual switch. That way I can turn on the DC-DC charger when I want, certainly when the engine is running but also when I'm on shore power.

Boris
 
I checked the boat, I have a Renogy DC-DC charger, NOT a Victron. I bought the 20 amp Renogy because it's cheaper: $102 vs $170, on Amazon.

They both have the alternator ON/power feature. Renogy has no Bluetooth, which I don't use.

The Renogy has a current limiting feature that has come in handy, a current limiter switch. This switch/port allows one to have a 1/2 rate charge, 10 amps. I use this switch to reduce the current to 10 amps when the boat is connected to shore power, so as to not overdrive the battery charger. Works well.

Boris
 
The Victron iPhone app has a demo library that lets you look at settings without connecting to a real product. You can check out the features and setting easily.

For Victron the alternator detection feature is called "Engine Shutdown Detection". You can set the detection voltages that kick off the DC-to-DC charger.

I have a Victron Orion-Tr Smart DC-DC Isolated 12/12-18A charger and it works great to charge my bank of lifepo4 batteries.

- tom
 
Here is my revised block diagram which I THINK is the way Bob explained it. Bob and Boris, do you agree?

m_of_Lithium_Battery_Charging_System_Revised.sized.jpg

Two things are missing: the locations and amperages of fuses, and (what was puzzling me reading the manual of the DC-DC charger but dawned on me reading Boris's post about the "motor running" switch) what the manual calls the "D+ ignition wiring." Specifically, the manual says, "The DC-DC will not power on or operate until the D+ ignition cable is connected to the ignition circuit where it will detect a 12V source to operate ON."

Now, to take my battery out of "shelf mode" I need to charge it WITHOUT the motor running. I THINK I can accomplish this by putting some 12 volt power into the D+ ignition input on the DC-DC charger, say a separate 12 volt battery connected to an automotive battery charger with the positive connected to the DC-DC positive input AND the D+ input, and the negative connected to the negative input. The DC-DC positive and negative outputs would be connected to the LiFePO4 battery's corresponding posts.

In real life, I will connect the "ignition on" wire from the outboard to the D+ on the DC-DC, AND Boris's work around to charge from shore power. It seems Renogy dropped the ball not to include some means of powering the DC-DC on when the motor is NOT running though.
 
schematic looks fine, but I would add a breaker between the DC to DC charger and Li battery (unless the DC to DC has a breaker on its output.

You could just hook up the guest charger with the start battery and battery to battery charger on the boat. That would be what you are doing at home or in the slip.
 
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