Has anyone gone all lithium for their battery battery bank to include the starter battery?
I want one bank wired in parallel with all Lithium batteries but I don't think it will push enough CCA to start the engine.
MQ
I am not an electrician nor a mechanic but my understanding is it takes very little cranking power to start our small engines. The main advantage for a dedicated start battery or reserve battery is the isolated/indepenant power source in a emergency.
Thanks, does anyone know if Maximum Continuous Discharging Current of 100A would be able to start the engine? That what Renogy Lithium batteries push.
I wrote Westerbeke and asked, and also have looked in the manual.
I trying to gain some perspective on your question and I'm not an electrician but if you operate a 1100 watt appliance (microwave) through an inverter, you would draw approx 100amps (1100watts at 12v = 91.6amps plus some conversion loss). Now you try and start the engine at the same time. Seems like the answer would depend on the state of charge and capacity of the lithium battery.
As Noah suggested, I think you're missing the point of a start battery.
Quote from: mark_53 on February 08, 2023, 11:43:17 AM
I trying to gain some perspective on your question and I'm not an electrician but if you operate a 1100 watt appliance (microwave) through an inverter, you would draw approx 100amps (1100watts at 12v = 91.6amps plus some conversion loss). Now you try and start the engine at the same time. Seems like the answer would depend on the state of charge and capacity of the lithium battery.
As Noah suggested, I think you're missing the point of a start battery.
I don't think this is an accurate statement. Lithium's will push 100A all the way until they die (unlike AGMs), so SOC doesn't matter with a lithium; you're going to get 100A to the starter regardless. A West Marine 105ah battery will send Cold Cranking Amps at 800A and Marine Cranking Amps at 1000A to the starter. On cold days my engine struggles more to start than when it is 90 out, and that's with the AGM I have. So, the question is, what is the minimum Amps required to be sent to the starter? Can a lithium do it at 100A? Sounds like they might not be strong enough.
"The maim advantage for a dedicated start battery or reserve battery is the isolated/Independant power source in a emergency." Yes, it to use the house bank without depleting the starter bank so your starter battery is full when you go to crank. I want this but I want a house bank of Lithium's since they basically have twice the power as an 100A AGM due to DoD, last for 4000 cycles instead of 300, and have a life expectancy of up to 10 years.
The solution to this, from what i've been reading, is to have a completely independent starter battery. Then you use a 12v 40A DC to DC battery Charger and charge the starter battery from the 2x Lithiums. The only thing you lose is the ability to quickly switch to the emergency start that taps into the house bank. I guess you would just move the 2 battery terminal wires over if you had to, but then I would still be hoping that the 100A from the lithium's would start the engine...
Switching the house bank to lithium would nearly double my ability to run all my offshore gadgets.
I also wouldn't start my engine with an inverter on running a microwave and all the lights and GPS/AutoPilot on. Just turn them off and start the engine.
It doesn't take much to start our engines. You should have no problem starting with a 800 CCA battery. I used a 550 CCA 80ah FLA battery to start. No problem.
MQ : Now that the airlines prohibit carrying a Laptop with a lithium battery in checked luggage because of possible fire, I don't think that I would want Lithium batteries on my boat!!!
A thought
RON— Not the same "Lithium". Different chemistry. He is referring to LiFePO4 batteries, which are more and more common in boats. Not the same as the lithium Ion batteries found in cars, computers, phones, and other electronic devices. Lithium ion batteries can overheat and catch fire, while LiFePO4 does not.
I'm going to venture forth with my opinions on this subject even though some may not agree. I'm right in the middle of reconfiguring my boat's battery and charging systems to incorporate LiFePO4 for the house bank. My recommendations to MQ are as follows:
1.First, spend some more time educating yourself about incorporating Lithium. As Maine Sail says, Lithium is not a drop-in replacement for lead acid. There's more to consider than you see at first glance. I'd recommend watching the video seminars on YouTube from Pacific Yacht Systems (Jeff Cote) on the subject (yes, I know, he's long winded, but there's good information in there.) Also Maine Sail has several good write-ups, as well as Nigel Calder's extensive writings and his videos on YouTube.
2.One of the above authors made a good analogy, which was that LiFePO4 batteries are like marathon runners, and lead-acid starter batteries are like sprinters. Starting an engine requires a sprinter – big push for a short duration. This is not what LiFePO4 batteries are designed for. They are good at providing a strong, steady output for long periods of time. The three authors above all seem to agree that using a LiFePO4 battery as a starter battery on a regular basis is not recommended.
3.You mentioned that you were going to have the DC to DC charger charging the starter battery from the house bank. In my opinion, that's backwards. Unless you are also using solar, the DC charger only comes into play when you are charging via the alternator. When you crank the engine, you are only draining the starter battery by a couple of percent in most cases, unless your engine requires some serious maintenance. (This is why most internally regulated alternators have a VERY conservative charging profile – it only takes a few minutes to fully recharge the starter battery.) So to me, it makes more sense to have the DC charger look to see when the starter battery has 13.6 V on it (i.e. it is being charged by the alternator), and draw from that side to also charge the house bank, which will likely be in more need of charging. The starter battery will be recharged in short order, and then the DC charger and alternator can focus on the house bank.
4.There are many misconceptions about Lithium batteries – especially the issue with flammability. Maine Sail does a good job of putting this to rest (as does Nigel Calder), clarifying that the LiFePO4 battery is very different that the earlier Lithium Ion batteries that made the news so often. The primary concern for fire with LiFePO4 would actually come from situations where a dead short in wiring occurred that would allow the battery to pump out vast amounts of current, melting the wiring. However most of the batteries being sold today have battery management systems that would shut down the battery in these situations. That BMS, combined with an appropriate Class T fuse in the main wiring configuration should greatly reduce this risk. The other situation to guard against is using a 1/2/both switch and combining a heavily discharged starter battery with a fully charged LiFePO4 bank. The large voltage difference would cause a big current spike, and again could lead to a wiring meltdown. In my configuration, I'm using a keyed switch hidden away from passengers that will allow me in an emergency use my house bank for starting the engine, but only after I first pull the fuse on the starter battery so that the two banks are never linked.
That's my nickel's worth. Is it worth installing LiFePO4? I think so – for nearly the same cost as replacing my 4 dying Trojan T-105's I'm getting about 220 amp hours, of which I can actually use about 175 AH on a regular basis (and more if I really need), whereas the Trojans gave me 420 AH, but I could only use about 35% of that on a regular basis or 147 AH (sometimes 200 AH if I pushed it hard, but you pay a price in longevity for that). Not to mention the far longer lifespan for the LiFePO4. And I can fit the two lithium batteries easily into the battery box, with enough room to also mount the DC to DC charger in there and do a nice, neat wiring job for my main unswitched bus, fuses, etc.
OK – I've stepped down off my soapbox...
Quote from: tmac on February 08, 2023, 06:14:20 PM
I’m going to venture forth with my opinions on this subject even though some may not agree. I’m right in the middle of reconfiguring my boat’s battery and charging systems to incorporate LiFePO4 for the house bank. My recommendations to MQ are as follows:
1.First, spend some more time educating yourself about incorporating Lithium. As Maine Sail says, Lithium is not a drop-in replacement for lead acid. There’s more to consider than you see at first glance. I’d recommend watching the video seminars on YouTube from Pacific Yacht Systems (Jeff Cote) on the subject (yes, I know, he’s long winded, but there’s good information in there.) Also Maine Sail has several good write-ups, as well as Nigel Calder’s extensive writings and his videos on YouTube.
2.One of the above authors made a good analogy, which was that LiFePO4 batteries are like marathon runners, and lead-acid starter batteries are like sprinters. Starting an engine requires a sprinter – big push for a short duration. This is not what LiFePO4 batteries are designed for. They are good at providing a strong, steady output for long periods of time. The three authors above all seem to agree that using a LiFePO4 battery as a starter battery on a regular basis is not recommended.
3.You mentioned that you were going to have the DC to DC charger charging the starter battery from the house bank. In my opinion, that’s backwards. Unless you are also using solar, the DC charger only comes into play when you are charging via the alternator. When you crank the engine, you are only draining the starter battery by a couple of percent in most cases, unless your engine requires some serious maintenance. (This is why most internally regulated alternators have a VERY conservative charging profile – it only takes a few minutes to fully recharge the starter battery.) So to me, it makes more sense to have the DC charger look to see when the starter battery has 13.6 V on it (i.e. it is being charged by the alternator), and draw from that side to also charge the house bank, which will likely be in more need of charging. The starter battery will be recharged in short order, and then the DC charger and alternator can focus on the house bank.
4.There are many misconceptions about Lithium batteries – especially the issue with flammability. Maine Sail does a good job of putting this to rest (as does Nigel Calder), clarifying that the LiFePO4 battery is very different that the earlier Lithium Ion batteries that made the news so often. The primary concern for fire with LiFePO4 would actually come from situations where a dead short in wiring occurred that would allow the battery to pump out vast amounts of current, melting the wiring. However most of the batteries being sold today have battery management systems that would shut down the battery in these situations. That BMS, combined with an appropriate Class T fuse in the main wiring configuration should greatly reduce this risk. The other situation to guard against is using a 1/2/both switch and combining a heavily discharged starter battery with a fully charged LiFePO4 bank. The large voltage difference would cause a big current spike, and again could lead to a wiring meltdown. In my configuration, I’m using a keyed switch hidden away from passengers that will allow me in an emergency use my house bank for starting the engine, but only after I first pull the fuse on the starter battery so that the two banks are never linked.
That’s my nickel’s worth. Is it worth installing LiFePO4? I think so – for nearly the same cost as replacing my 4 dying Trojan T-105’s I’m getting about 220 amp hours, of which I can actually use about 175 AH on a regular basis (and more if I really need), whereas the Trojans gave me 420 AH, but I could only use about 35% of that on a regular basis or 147 AH (sometimes 200 AH if I pushed it hard, but you pay a price in longevity for that). Not to mention the far longer lifespan for the LiFePO4. And I can fit the two lithium batteries easily into the battery box, with enough room to also mount the DC to DC charger in there and do a nice, neat wiring job for my main unswitched bus, fuses, etc.
OK – I’ve stepped down off my soapbox…
Tom,
Thanks for the great advice. After a ton more research and contacting Renogy it sounds like the 100A a LiFePO4 produces will not work for engine crank ups, so I'll be going with a 2x 100Ah LiFePO4 House Bank and 1x 105Ah AGM starter bank with DC to DC charger option from the starter bank to the house bank.
------------
I've been watching Pacific Yacht Systems and that's where I got the idea for the DC to DC charger. You are correct about the DC to DC going from the Starter Battery to the House Bank, I miss spoke. That's is what I intend on doing. I have 200 watts of solar also, which I could re wire to the starter battery in the event the alternator craps out and I need the starter battery at full power.
MQ
Save some money and get a plain old flooded lead acid "maintenance-free" (sealed) battery for your starting battery. IMO, better choice than AGM for this purpose.
Quote from: Noah on February 09, 2023, 12:00:38 AM
Save some money and get a plain old flooded lead acid "maintenance-free" (sealed) battery for your starting battery. IMO, better choice than AGM for this purpose.
I'm going to be using one of my House Bank AGM for the starter bank, when I put the lithium's in, so don't have to buy another starter battery. I'll keep the other on board and charge every once in while to have an extra starter battery, until i feel comfortable with lithium's. Just bought all the stuff Renogy, i'll make a YouTube video of the install and follow up on how it worked. Should arrive next week.
Heading out this weekend, #### weather, so hopefully this parallel set up I did doesn't bite me in the ass.
Gents,
FYSA, from Westerbeke about the cranking amps for M25XP. Lithiums which supply 100A are not recommended.
Thank you for your inquiry. Westerbeke recommends an 800 to 1000 CCA starting battery be connected to your M25XP. The amount of starter motor amperage draw running that is posted in the technical manuals specification for the product is listed as 46 Amps, see page 33 (38 of the .pdf) of the manual found at this link 200155_rev2_m12-m35_technical_man.pdf (westerbeke.com) to our web site. However, it is important you understand that the amperage will vary based on the cable size, cable condition, cable length, starter condition, as well as the overall condition of the engine and the other circuitry in the engines DC electrical system. Also note that the in rush current draw may on initial start can easily be 5 to 10 times that amount, hence the 800 to 1000 CCA recommendation. For more help we suggest you consider seeking the advice of your local Westerbeke representative.
MQ
Overkill. Mine cranks-up instantly with a flooded group 24 Penn 650 battery with 550 CCA.
I used a group 78 side post battery for my dedicated start battery. The shorter and larger wire runs made a noteable difference in cranking performance (mounted under the aft berth).
Quote from: waughoo on February 09, 2023, 07:40:59 PM
I used a group 78 side post battery for my dedicated start battery. The shorter and larger wire runs made a noteable difference in cranking performance (mounted under the aft berth).
Waughoo,
I like the sound of that set up, do you have photos of that placement? Are you using a charger relay, or is the starter battery its own bank?
Sound like a good way to get a third House Battery under the saloon seat.
V/R,
MQ
I used a victron dc to dc charger from the house bank to the start battery. All my charging sources go to the house bank. I elected to go with the side post battery so I could fit it easily under the aft berth. It is just opposite the vertical wall at the aft end of the footwell of the aft cabin.
I do have photos but none handy at the moment.
Here is a webinar on lithium batteries hosted by the GLCC School that may be of interest. (Great Lakes Cruising Club)
https://www.glccschool.com/content/mx00102-h-lithium-battery-technology-cruising-boaters
Watch live and ask questions, then next day get a link to the recording for review. I've found the GLCC webinars to be very helpful. Many more topics than the battery one. FWIW my favorite is the weather webinars, I now can read and interpret weather maps. Have much more confidence in cruise planning.
Jim
Quote from: waughoo on February 10, 2023, 08:43:43 AM
I used a victron dc to dc charger from the house bank to the start battery. All my charging sources go to the house bank. I elected to go with the side post battery so I could fit it easily under the aft berth. It is just opposite the vertical wall at the aft end of the footwell of the aft cabin.
I do have photos but none handy at the moment.
Thats make more sense to me, to send power from the house bank to the starter, since it would only be a small amount to top it back up. My stuff is arriving today so i'm going to start the install.
Please send the pics when able.
V/R,
MQ
Here are some photos. Built a custom shelf epoxied to the hull to hold the battery in the aft area. There are two vertical walls port and starboard that serve to corale the battery and provide mounting surfaces for the fuses, RBS on one side and the victron B2B on the other.
After it all got wired up, I removed the 1 2 Both switch replacing it with the switches for the RBSes (one for engine start and one for house panel). The switch on the far right of that panel is for my mast head tri color/anchor/strobe. The panel breaker for anchor turns it on and the three way switch shown closes its function.
With regards to the charging power all going to the house bank, I MUCH prefer this to the other way around. If one increases their alternator charging amps and they have it going to the start battery, more B2B chargers need to be added to take advantage of that extra power. The start battery really only needs a small amount after each use. I went with an 18 amp B2B as it was a bit cheaper and honestly, unless the battery was COMPLETELY dead, I will never get to a full 18 amps.
Putting alt charging direct to the house does also require a high quality remote regulator that has the ability to specifically set the charge profile for lithium and monitor alternator case temps, but any good house bank charging system should be remote regulated for a boat that is meant to spend multiple nights away from a dock.
Let me know if you have any questions about the set up.
This article while very long has all the details you are looking for.
https://marinehowto.com/drop-in-lifepo4-be-an-educated-consumer/ (https://marinehowto.com/drop-in-lifepo4-be-an-educated-consumer/)
Lithium bank installed with separate AGM for starter. Today I'll add a Positive Bus for the House bank and then install the DC to DC charger. So far it's all working. I'm planning a 4 day sail this weekend to test it all out. Looking much cleaner than before. If I were to move the starter battery to the Aft Cabin I could fit 4 Lithium's in the current house bank location. Only issue is those batteries are $650 a piece. But right now I have essentially twice the power in the house bank with those 2 Lithiums.
Quote from: waughoo on February 13, 2023, 10:03:44 PM
After it all got wired up, I removed the 1 2 Both switch replacing it with the switches for the RBSes (one for engine start and one for house panel). The switch on the far right of that panel is for my mast head tri color/anchor/strobe. The panel breaker for anchor turns it on and the three way switch shown closes its function.
Waughoo,
That's a nice setup. Have you had any issues with moisture in that location? I typically have water sitting back there due to the stuffing box and general condensation.
MQ
I did have some standing water back there in the past but have since drilled a limber hole under the engine pan to get the water to transit forward to the main bilge. I also have a dripless shaft seal so what is back there is fresh water.
Quote from: senorquill on February 08, 2023, 09:51:07 PM
Quote from: tmac on February 08, 2023, 06:14:20 PM
I'm going to venture forth with my opinions on this subject even though some may not agree. I'm right in the middle of reconfiguring my boat's battery and charging systems to incorporate LiFePO4 for the house bank. My recommendations to MQ are as follows:
1.First, spend some more time educating yourself about incorporating Lithium. As Maine Sail says, Lithium is not a drop-in replacement for lead acid. There's more to consider than you see at first glance. I'd recommend watching the video seminars on YouTube from Pacific Yacht Systems (Jeff Cote) on the subject (yes, I know, he's long winded, but there's good information in there.) Also Maine Sail has several good write-ups, as well as Nigel Calder's extensive writings and his videos on YouTube.
2.One of the above authors made a good analogy, which was that LiFePO4 batteries are like marathon runners, and lead-acid starter batteries are like sprinters. Starting an engine requires a sprinter – big push for a short duration. This is not what LiFePO4 batteries are designed for. They are good at providing a strong, steady output for long periods of time. The three authors above all seem to agree that using a LiFePO4 battery as a starter battery on a regular basis is not recommended.
3.You mentioned that you were going to have the DC to DC charger charging the starter battery from the house bank. In my opinion, that's backwards. Unless you are also using solar, the DC charger only comes into play when you are charging via the alternator. When you crank the engine, you are only draining the starter battery by a couple of percent in most cases, unless your engine requires some serious maintenance. (This is why most internally regulated alternators have a VERY conservative charging profile – it only takes a few minutes to fully recharge the starter battery.) So to me, it makes more sense to have the DC charger look to see when the starter battery has 13.6 V on it (i.e. it is being charged by the alternator), and draw from that side to also charge the house bank, which will likely be in more need of charging. The starter battery will be recharged in short order, and then the DC charger and alternator can focus on the house bank.
4.There are many misconceptions about Lithium batteries – especially the issue with flammability. Maine Sail does a good job of putting this to rest (as does Nigel Calder), clarifying that the LiFePO4 battery is very different that the earlier Lithium Ion batteries that made the news so often. The primary concern for fire with LiFePO4 would actually come from situations where a dead short in wiring occurred that would allow the battery to pump out vast amounts of current, melting the wiring. However most of the batteries being sold today have battery management systems that would shut down the battery in these situations. That BMS, combined with an appropriate Class T fuse in the main wiring configuration should greatly reduce this risk. The other situation to guard against is using a 1/2/both switch and combining a heavily discharged starter battery with a fully charged LiFePO4 bank. The large voltage difference would cause a big current spike, and again could lead to a wiring meltdown. In my configuration, I'm using a keyed switch hidden away from passengers that will allow me in an emergency use my house bank for starting the engine, but only after I first pull the fuse on the starter battery so that the two banks are never linked.
That's my nickel's worth. Is it worth installing LiFePO4? I think so – for nearly the same cost as replacing my 4 dying Trojan T-105's I'm getting about 220 amp hours, of which I can actually use about 175 AH on a regular basis (and more if I really need), whereas the Trojans gave me 420 AH, but I could only use about 35% of that on a regular basis or 147 AH (sometimes 200 AH if I pushed it hard, but you pay a price in longevity for that). Not to mention the far longer lifespan for the LiFePO4. And I can fit the two lithium batteries easily into the battery box, with enough room to also mount the DC to DC charger in there and do a nice, neat wiring job for my main unswitched bus, fuses, etc.
OK – I've stepped down off my soapbox...
Tom,
Thanks for the great advice. After a ton more research and contacting Renogy it sounds like the 100A a LiFePO4 produces will not work for engine crank ups, so I'll be going with a 2x 100Ah LiFePO4 House Bank and 1x 105Ah AGM starter bank with DC to DC charger option from the starter bank to the house bank.
------------
I've been watching Pacific Yacht Systems and that's where I got the idea for the DC to DC charger. You are correct about the DC to DC going from the Starter Battery to the House Bank, I miss spoke. That's is what I intend on doing. I have 200 watts of solar also, which I could re wire to the starter battery in the event the alternator craps out and I need the starter battery at full power.
MQ
The best value in a 100Ah drop-in right now are the Epoch LFP Batteries (https://www.epochbatteries.com/?rfsn=7030270.54d2cb). Amazing build quality a 1.2C continuous BMS(200A for as long as 30 seconds OR 285A FOR 1S), waterproof, BLUETOOTH BMS, cell compression, CAN etc.. Kilovault are also Excellent. You could not pay me to install or own anything Renogy. Way higher than average failure rate but that is not the worst of it . Their customer support is the worst I have seen in any industry. We used to install customer supplied Renogy products to help our customers save money. We had to stop offering this as we were getting blamed for the failures and not a single one had to do with the installation.. I don't think a single customer got their warranty covered...
Hi Seniorquill, I know this is an old thread but a quick question. Did you replace your alternator for an externally regulated one as part of this install?
Here is a link that I found very interesting. He has been adding lithium batteries and upgrading so may be best to watch in chronical order. Need to scroll down to the episodes with batteries. Disclaimer, I've only watched and haven't bought or installed anything.
https://www.youtube.com/playlist?list=PLsT7_jPsZM5pFpq8RX0oxjibknM2Gz361
FWIW I have added their way of tying the alpine butterfly to my repertoire of knots. It's like doing a magic trick.
Jim
Quote from: KeelsonGraham on January 10, 2024, 03:36:16 PM
Hi Seniorquill, I know this is an old thread but a quick question. Did you replace your alternator for an externally regulated one as part of this install?
Keelson... looked like your question got buried across the page break. Not sure if the OP will get back to you, but what question are you looking for?
It's because I read somewhere that you need an alternator with an external regulator for a lithium setup. So, I was going to ask the OP what he did about this aspect of the install.
Keelson,
If you plan to connect your alternator output directly to the house bank, you will indeed need an externally regulated alternator. The charge profiles and acceptance rate of Lithium banks is different enough that an internally regulated alternator is incompatible. If you are looking to get SOME alternator charging into the house bank via an alternator connected to a lead acid start battery, you could use a dc to dc charger to feed correctly configured charge profiles to a lithium house bank. This does limit the ability to drive lots of amps from a high output alternator to those bank, but it does allow for a simpler implementation when one doesn't already have an externally regulated alt.
Thank you. That's good to know. It'll certainly add a major cost to the conversion to lithium.
I do not have an externally regulated alternator.
I added 2 more Lithiums for a total of 400ah in the house bank. I moved the starter battery to the aft berth. I have a DC-DC Convertor that sends power from the Alternator to the House bank if I need it. The switch for the DC-DC is on the nav station. I have 400 watts of solar power that feed into the house bank so I never have to use the DC-DC. For a back for my starter battery, I have a West Marine 120v battery charger. So if the alternator ####s out, I can still charge my starter battery using the house bank of lithiums and the inverter. That West Marine device also does a 40amp jumper function. I'll post pics of the final project, but over all it has worked great.
(You need a strong alternator to compensate for this setup, since it sends power to the Starter Batt and to the DC-DC at the same time.).
Just sail 700 miles from Destin to Stuart Florida. Heading down to West Palm Beach to cross over to The Bahamas for the season. Pics to follow.
MQ
Final install pics.
4 Lithiums under the settee for 400AH of house power
AGM Starter in aft cabin above engine
West Marine Charger for pulling house bank power to the starter batt and to jump engine.
DC-DC 40amp, for charging house bank off the alternator.
I ran that initial setup for several months to find issues before going with 4 lithiums. The main issue was not being able to charge the starter battery if the alternator goes down. All my other power sources go to the litium bank, ei, Shore power, solar. The West Marine charger solves this.
MQ