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Lead acid to lithium, charging & Bow Thruster

TFlight

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Joined
Feb 26, 2022
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5
Sailboat Electrical upgrade

I’m new to the forums and want to thank you Will for all your great videos and putting this forum together.

I am considering revamping the electrical system on my sailboat by swapping my lead acid 470Ah House Bank (House batteries are in need of replacing) for 200 or 300Ah of lithium and adding 200W of solar for a total of 405 watts. I was also considering the Victron Energy Orion-Tr Smart 12/12-Volt 30 amp 360-Watt DC-DC charger to assist with my 80 amp Hytachi alternator and new lithium bank. I feel many questions coming on. ?‍??

Currently I have 3 Banks of batteries:

1. The House Bank consists of 4 x lead acid Crown CR235 6 volt 235Ah batteries connected in series parallel for 12 volts 470 amps. They are in need of replacing
2. The Bow Thruster Battery Bank is a lead acid 904D 1050CCA installed in 2015. The Bow Thruster (Lewmar 140TT 3hp) is Rarely maybe once a week and when it is used it’s for less than 30 seconds or a minute at most. The Bow Truster is a Lewmar 140TT 3hp 12V motor rated 280 Amps on the cable size diagram.
3. Yanmar Diesel Engine Start Battery is a lead acid Group 24 12V 780 CCA.


My boat systems consist of the following:

A) The engine alternator is a Hytachi 80 Amp alternator stock to the Yanmar 4Jh4E 55hp engine.
B) I have a Mase 4.04 3.2KW 120V 60hz Generator for AC and to power Magnum MS 2000W inverter, 100 Amp Charger.
C) Magnum MS2000 pure sin wave 120V 60hz 2000W, 12V 100Amp charger. Magnum Energy ME-RC 50 Remote.
D) Solar, I only have one 205W Kyocera Polycrystalline panel but have room for one more 200W panel.
E) Blue Sky Charge controller 25A 12Vix. ( I was told it could handle 405W of solar because you never get rated power out of the panels. I hope that’s true?) I also have the Blue Sky IPN Remote.


The current setup as I understand it:

The engine’s Hitachi 80A alternator charges the Engine Start Battery and connects through a parallel
Solenoid, as long as the circuit breaker for parallel is on, and charges the House Bank.
The House Bank, when charging then charges the Bow Truster through a Blue Seas ACR.
I’m really not sure it’s the best set up but that’s how it is now with the lead acid batteries.


What I would like to do is replace my 4 lead acid (470Ah total) batteries with Chins or equivalent lithium 200Ah battery. I know that’s a bit of a decrease in total amperage but given the low usable amps of lead acid I don’t think it’s too bad.


1st question could I incorporate the House and the Bow Thruster Bank by adding another 100Ah of lithium in parallel with the 200Ah House Bank, bring it up to 300Ah and simplifying down to just 2 battery banks, the House and Starer Bank?

1a) Would the lithium be capable of the discharge rate required of the 3hp Bow Truster for short burst of infrequent use?


2) If I don’t combine the House and Bow Thruster Bank, and leave it as a lead acid battery, what is the best way to charge the Bow Truster Battery? An ACR off the Start Battery? I’m planning on a DC-DC charger for the lithium House Bank (see 3). Note the two banks are within a few feet of each other and the Bow Thruster has a dedicated fuse block and Perko switch.


3) If I go with the Victron Energy Orion-Tr Smart 12/12-Volt 30 amp 360-Watt DC-DC charger to charge my lithium House Bank from my Hytachi 80 amp alternator will this be too large for the alternator? Will it cause the alternator to overheat or prematurely fail? It’s my understanding you can safely only get ½ of the rate output of a standard alternator. Should I use a 20 amp DC-DC charger?


4) For winter storage, the batteries I’m looking at do not have a BMS with low temperature cut-out for charging. How do I best address this issue? Disconnect all charging sources when bellow 0’ C or is there a low temperature sensor that can be added to the Blue seas solar charge controller and DC-DC charger?



I thank you for your time and input,
 
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1. Best to keep the FLA for the bow thruster and maintain charge through the house bank. As Mr. Sandals said LFPs generally don't handle high current situations too well.

2. That is an appropriate solution to charge your bow thruster FLA. What's the LOA of your vessel? I would have expected that the bow thruster battery would have been closer to the bow and the house bank closer to the stern, but what do I know. 280 amps is a good bit of current to go from one end to the other.

3. Good idea to maintain the health of the alternator by limiting its current output.

4. Cold temps may not be an issue depending on your location. I set my Victron MPPT (via it's Bluetooth connectivity) to limit charging of my LFPs to 13.4 during "long winter naps". The Victron also has a low temp cutout feature.

The more PV the better, but since you've a generator as backup, you should be in good shape to augment a 400 watt PV setup.
 
Quick reply.

A drop in battery like the Chins will not power the thruster, not enough starting or running current .

Keep the 904D, charge via the ACR from the starter battery.

The 80 Amp alternator should be OK with the typical 35 amp input of the Orion.

Replace the solar controller with something better, Victron recommended.

Without battery low temp cut off its easy to disable the Orion and Victron solar controller via the remote inputs using thermostatic switches.

It would be preferred to use battery that had thermal protection ( high temp ) built in.

Unless you have power issues, like not enough, consider keeping the lead acid house bank, leaving the lithium update untill they need to be replaced.
Up date the solar, more panels and a true mppt controler. Consider using the Orion as the charger, rather than from the alternator, for the lead house bank.

Mike
 
I thank you for your time and feedback,

My boat has a LOA of 41 feet. The House, Bow Thruster and Start batteries are all within 5 feet or less of each other. The Bow Thruster is about 15 feet from it’s battery.

Thank you all for validating my concern of the Bow Thruster’s heigh current draw on LFP’s. I will continue to keep the Bow Thruster on its’ own its’ dedicated 904D FLA battery. I’ll also leave the House Bank to charge the Bow Thruster Bank through the Blue Seas ACR.

My FLA House Bank is in need of being replaced and that being the catalyst for this whole project.
The LiFePO4 batteries I’m considering do have a height temperature cut-out for charging and I will use one of the methods mentioned for low temp cut-out.

I do have a question on battery bank build.
1) I’m looking at starting with a 200Ah House Bank. Is there an advantage or disadvantage of using two 100Ah batteries verses one 200Ah battery if battery cost are the same and space / storage is not a factor.

2) If I latter, say within 6 months, want to add to the Bank do I have to match the Bank in size. Example If 100Ah batteries where used should I only add in 100Ah increments, likewise if using one 200Ah battery only add in 200Ah increments up to the allotted manufactures recommendation?

Thanks again
 
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I suggest you lookup the actual Amps requirement of the bow thruster. Currently advertised units are 2.2kW. That translates to "only" 170 amps at 13v. If that is the case, then 3x 100 amp/hr batteries in parallel should handle the thruster (and house) even with one of them disconnected. It would be much simpler to have all the batteries the same.

I looked into using the Victron ACR between Pb and LFP. The default turn on voltage is 13v, and thus connects them at most all LFP voltages (and consumes 0.2 amps doing it). That was too much 7x24 waste for me.
 
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And make sure you open that circuit breaker that combines the starter<->house when under power. It is unlikely that the Hitachi will survive charging the LFP.
I have one as well, and while it reduces its charging voltage as the alternator heats up, whether it will reduce it low enough to save the alternator is an experiment you can only run once. I have left mine open, and only charge with solar and Orion DC-DC.
 
I suggest you lookup the actual Amps requirement of the bow thruster. Currently advertised units are 2.2kW. That translates to "only" 170 amps at 13v. If that is the case, then 3x 100 amp/hr batteries in parallel should handle the thruster (and house) even with one of them disconnected. It would be much simpler to have all the batteries the same.

I looked into using the Victron ACR between Pb and LFP. The default turn on voltage is 13v, and thus connects them at most all LFP voltages (and consumes 0.2 amps doing it). That was too much 7x24 waste for me.
My boat is on the hard right now finishing up winter storage. When I splash in a few weeks I’ll try and get an current draw on the bow thruster to have a better idea of it’s thirst. I thought the amperage indicated on the cabling chart for the 2.2Kw (3hp) motor was a bit heigh. It would be great if I could add a 100Ah LFP for a total of 300Ah there by having that extra 100Ah battery contributing to the House Bank since I barely use the Bow Thruster.
 
And make sure you open that circuit breaker that combines the starter<->house when under power. It is unlikely that the Hitachi will survive charging the LFP.
I have one as well, and while it reduces its charging voltage as the alternator heats up, whether it will reduce it low enough to save the alternator is an experiment you can only run once. I have left mine open, and only charge with solar and Orion DC-DC.
Once I have the lithium installed I will open the paralleling circuit breakers and tape a note on them so nobody accidentally flips them on.
I plan on charging the LFP’s through a Victron Energy Orion-Tr Smart 12/12-Volt 30 amp 360-Watt DC-DC charger or maybe a Renogy 20 amp DC-DC charger as well by solar or the Magnum MS2000 inverter/charger.
 
If I was you, what I'd initially do is as you describe, have 30A DC:DC feeding your lithium bank. However, down the road, I would consider swapping out your alternator for a higher power unit, along with an advanced regulator, so your engine can directly charge the lithium batteries. You can then re-use the Orion DC:DC charger to keep your thruster and/or starting battery charged. Let's just say that it's awfully nice to see current flowing into your LiFePO4 bank at a continuous 100A+.
 
Sailboat Electrical upgrade

I’m new to the forums and want to thank you Will for all your great videos and putting this forum together.

I am considering revamping the electrical system on my sailboat by swapping my lead acid 470Ah House Bank for 200 or 300Ah of lithium and adding 200W of solar for a total of 405 watts. I was also considering the Victron Energy Orion-Tr Smart 12/12-Volt 30 amp 360-Watt DC-DC charger to assist with my 80 amp Hytachi alternator and new lithium bank. I feel many questions coming on. ?‍??

Currently I have 3 Banks of batteries:

1. The House Bank consists of 4 x lead acid Crown CR235 6 volt 235Ah batteries connected in series parallel for 12 volts 470 amps.
2. The Bow Thruster Battery Bank is a lead acid 904D 1050CCA. The Bow Thruster (Lewmar 140TT 3hp) is Rarely maybe once a week and when it is used it’s for less than 30 seconds or a minute at most. The Bow Truster is a Lewmar 140TT 3hp 12V motor rated 280 Amps on the cable size diagram.
3. Yanmar Diesel Engine Start Battery is a lead acid Group 24 12V 780 CCA.


My boat systems consist of the following:

A) The engine alternator is a Hytachi 80 Amp alternator stock to the Yanmar 4Jh4E 55hp engine.
B) I have a Mase 4.04 3.2KW 120V 60hz Generator for AC and to power Magnum MS 2000W inverter, 100 Amp Charger.
C) Magnum MS2000 pure sin wave 120V 60hz 2000W, 12V 100Amp charger. Magnum Energy ME-RC 50 Remote.
D) Solar, I only have one 205W Kyocera Polycrystalline panel but have room for one more 200W panel.
E) Blue Sky Charge controller 25A 12Vix. ( I was told it could handle 405W of solar because you never get rated power out of the panels. I hope that’s true?) I also have the Blue Sky IPN Remote.


The current setup as I understand it:

The engine’s Hitachi 80A alternator charges the Engine Start Battery and connects through a parallel
Solenoid, as long as the circuit breaker for parallel is on, and charges the House Bank.
The House Bank, when charging then charges the Bow Truster through a Blue Seas ACR.
I’m really not sure it’s the best set up but that’s how it is now with the lead acid batteries.


What I would like to do is replace my 4 lead acid (470Ah total) batteries with Chins or equivalent lithium 200Ah battery. I know that’s a bit of a decrease in total amperage but given the low usable amps of lead acid I don’t think it’s too bad.


1st question could I incorporate the House and the Bow Thruster Bank by adding another 100Ah of lithium to the House Bank bring it up to 300Ah and simplifying down to just 2 battery banks the House and Starer Bank?

1a) Would the lithium be capable of the discharge rate required of the 3hp Bow Truster for short burst of infrequent use?


2) If I don’t combine the House and Bow Thruster Bank, and leave it as a lead acid battery, what is the best way to charge the Bow Truster Battery? An ACR off the Start Battery? I’m planning on a DC-DC charger for the lithium House Bank (see 3). Note the two banks are within a few feet of each other and the Bow Thruster has a dedicated fuse block and Perko switch.


3) If I go with the Victron Energy Orion-Tr Smart 12/12-Volt 30 amp 360-Watt DC-DC charger to charge my lithium House Bank from my Hytachi 80 amp alternator will this be too large for the alternator? Will it cause the alternator to overheat or prematurely fail? It’s my understanding you can safely only get ½ of the rate output of a standard alternator. Should I use a 20 amp DC-DC charger?


4) For winter storage, the batteries I’m looking at do not have a BMS with low temperature cut-out for charging. How do I best address this issue? Disconnect all charging sources when bellow 0’ C or is there a low temperature sensor that can be added to the Blue seas solar charge controller and DC-DC charger?



I thank you for your time and input,
1) Keep lead acid for bow thruster. Its there, wired and working... no real advantage to making any changes.

2) The ACR is fine for that, between the start battery and thruster battery. Really you are just topping off your start battery and bow thruster battery. They shouldn't be drained all that much.

3) 30 amp Orion is fine. You could even do 2 Orions for 60 amp but if you are going to spend that money might as well consider jumping up to a better alternator with a separate controller. It also depends on how much you use your house bank. With solar, generator, and alternator I would start with the one Orion and see what tweaks I need to make down the road.

4) The Orion will only start charging when there is a charge voltage from the alternator. If you are never running your engine below 0 then you don't need temp shut off for that. On the solar side go with a charge controller that has its own low temp cutoff like Victron.

The alternator should go to a switch and then the start battery and connect to the house via the Orion. There should not be a combine option on a switch for those two any more. You could rewire your current combine switch to the engine and thruster battery for a backup.

I would draw everything out. It can get confusing.

My 2 cents... you will probably get 15 different opinions. Good luck.
 
280ah lifepo4 12v with an Xaioxiang 200a BMS drives my 12v thruster all day but I did use heavy cables when I built the battery. I pull 170a when using the thruster. Have been using this battery for a year.20220723_130319.jpg
 
Lithium is actually way better as a thruster battery then LA and can supply high currents

The issue are the limitations of cheap BMS.
 
Bypass the BMS? Fast blow T class protected of course. Slow blow ANL as well to meet thruster/ windlass
run current plus 25%.
 
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Bypass the BMS? Fast blow T class protected of course. Slow blow ANL as well to meet thruster/ windlass
run current plus 25%.
Bypassing the bms will of course make the install non ABYC or ISO compliant
 
search out BBMS on youtube for another option. I was designed by a sailor (also engineer) for getting lead and lithium "banks" to dance together well.... in particular if one is already running with lead and all the charging parts that come with that...... and one wants then to add/update your boat battery banks via putting some lithium in there.

THis way you wont have to change your alternator... or can upgrade to higher output alt. without cost of a high output "smart" one needed for lithium charging.
 
search out BBMS on youtube for another option. I was designed by a sailor (also engineer) for getting lead and lithium "banks" to dance together well.... in particular if one is already running with lead and all the charging parts that come with that...... and one wants then to add/update your boat battery banks via putting some lithium in there.

THis way you wont have to change your alternator... or can upgrade to higher output alt. without cost of a high output "smart" one needed for lithium charging.
This is the dc dc from starter to Li. I presume.

It’s not a very good approach in my view. Lithium is a whole battery system redesign to be safe efficient and effective.
 
This is the dc dc from starter to Li. I presume.

It’s not a very good approach in my view. Lithium is a whole battery system redesign to be safe efficient and effective.
you know what they say about ass-u-me lol. BBMS is so new of a concept and product it is best not to assume anything.
 
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