Our move to lithium with specific questions relating to keeping existing components

[Baronkrak]

Originally Posted by Chaff

Hi everyone,....
Due to VERY restrictive AUS/NZ standards pretty much must be Victron, ...
Al

Definitely the right move to build a lithium installation to a Standard. It makes the installation tradeable, insurable and safer.

[jbinbi]

Originally Posted by The Yacht Rigger

We recently released this video regarding lithium battery installs, I think you will find it helpful.
Please ask any questions in the comments on the video as our electrical team is all in the loop right there.
https://youtu.be/2r6NbG73qZg?si=zJzWdVTehUbTHoYg

Very interesting to see what a professional electrician does. Thanks.

[Zil]

Hello, Chaff. I can highly recommend the newest Orion-XS. It operates at a much lower temperature than the Orion-TR 30. The XS can be adjusted to different amperes up to 50 amperes. With such a large proposed bank of LiFePo4, charging directly with an alternator could prove to be expensive. The Orion devices do protect the alternator.

[Nicholson58]

We installed Blue Heron LiFePo. The sales guy, Hank, assisted in evaluating all of our devices and lining up the update software, dongles, cables, BMS etc. He was excellent in assisting during design and installation. We did the project in Trinidad with all items shipped in. (3 rd world). Total including battery box mods was five days.

Hank@starboardlanding.com

House and start banks - 24 volts.

[CarlF]

As others have suggested, I'd get the Victron 50 amp DC-DC charger. Leave your alternators as they are now. 50 amp draw won't overheat the alternators. And 2x50 (100 amps) will noticeably help charging the house bank. No need to change regulator.

After you've lived with the setup for a year you can decide if you want to go for big alternators and a more fully featured regulator - in which case you'll still use the Victron DC-DC charger but maybe in a different way.

The reason to go big on battery capacity is to let you stay longer in an anchorage in cloudy conditions without starting an engine or generator. I can go three days at anchor with little sun. It also lets me run the watermaker and washer/dryer when I want rather than only when there's sun. I'd even consider going to 1200AH (I have 1500AH)

[CaptainRivet]

Originally Posted by Zil

The Orion devices do protect the alternator.

That's the biggest wrong information on all of this DC2DC chargers. The onlybthing they do is limit the current. Ask how many cruisers with DC2DC smoked their alternator in the actual heat waves in the med...a lot.

The alternator dies from heat and no DC2DC charger is controlling and checking the heat of the alternator, it only limits the current.
Maybe 1% of DC2DC fitters actually use a temp probe and at the highest ambient temp motor with 1500RPM and measure the amount of current the alternator in this installation can provide to stay below 100 degrees celcius constantly or used a temp probe on their AGM setup before and monitored the alternator temps under different conditions.
That's is what you need to actually do to spec your DC2DC right but nearly noone does that.

What's done in reality is that it's expected !!! that your alternator can do 50% of its rating continious and that how the DC2DC is speced. Well a lot can handle that, several not in 40 degrees ambient greece when motorsailing with 1500 RPM and smoke there alternator because it's not protected but you think it is.

Don't understand why victron doesn't offer a temp probe for the 50A Orion XS that would simply reduce current when alternator gets too hot, would be easy to do and actually a real protection plus what I would have expected from the marketing hype the made around it...

And others like the Mitsubishi 115A and 125A valeo actually have internal temp protection and don't need a DC2DC at all. Means all newish volvo and yanmars, betas, Venus with serpentine belt don't need an DC2DC, total waste of money.
Charge via argofet splitting diode starter and house in parallel is much better and not unnecessary limit the alternator to 30 or 50A for 300Euro when it actually can do 85A with a 130Euro argofet.

[GreenWave]

Captain Rivet
The reason there is. It temp probe to limit current output on the DC chargers is because this is a very inefficient way to charge anything from your alternator. Use of a good regulator ties into the batteries, charger, and BMS is way to go

For the OP, I question the need for multiple starter batts. Just use one and then setup way for emergency start from house. Down the road you can even just run everything off the house including engine start. I’d also get a Victron charger. Will be better for their batts and more options and controls.

[CaptainRivet]

Originally Posted by GreenWave

Captain Rivet
The reason there is. It temp probe to limit current output on the DC chargers is because this is a very inefficient way to charge anything from your alternator. Use of a good regulator ties into the batteries, charger, and BMS is way to go

I am fully aware of this. BUT reality locks different.

Manufacturers simply using the DC2DC way as it's for them the less costs as they can keep everything like lead installation and just add DC2DC.
Also a lot owners are simply afraid of all the complexity with an external regulated alternator refit, especially if you have newer volvo engines with the dreaded MDi box and it's D+

So the DC2DC sell really well and I saw dozens incl..my own on 115A Mitsubishi and Valeo alternator that castrated it to 30A even it can do cont 85A and has its own temp protection means the DC2DC is useless.
Same by the way in the RV world.
So victron would have been smart if they just add a temp probe that let the DC2DC know when the alternator is getting too hot to reduce the current. All the features you need are on board of the XS series (not the old 30A heating brick) and that should have been the real deal as you can really max the existing alternator out without hacking into the existing installation and on the other side really protect the alternator.

[Nicholson58]

Note my post #19. We installed lithium house and start. We have Balmar 624 external regulators on all alternators. These are easy to install and programmable. I have also converted internal to externally regulated. This is easy and there are many YouTube videos to help. Our house and start banks are in parallel. This gives a high available instant starting current for our 115 HP Westerbeke, 80 amps at 28 volts max. This avoids the DC to DC power supply and the real estate, cost to own and install. This also eliminates the power lost ripening the DC DC device. You really need programmable charging devices or you are relying solely on the BMS. This is not a good idea nor is it efficient. Your alternator external controller lets you operate the alternator at less than full rated output. Unless your alternator is rated for continuous full load output it will burn up. I lost two this way. Mine are all set to 50% now and quite happy. If you have solar chargers these also need to be programmed for lithium. Lithium batteries are tremendous devices but you must treat them properly or just stay with lead.

[Chaff]

Originally Posted by CaptainRivet

Charge via argofet splitting diode starter and house in parallel is much better and not unnecessary limit the alternator to 30 or 50A for 300Euro when it actually can do 85A with a 130Euro argofet.

So what protects the alternator from overheating if u just chuck in an argofet?

[more]

Originally Posted by Chaff

So what protects the alternator from overheating if u just chuck in an argofet?

if you buy in EU alternator ,
The alternator is protected from overheating by several features and components, including:

Cooling Vents and Fans: Many alternators are designed with built-in cooling vents to allow air circulation, which helps dissipate heat. Some alternators also have fans that help move air through the unit, further cooling it.

Thermal Protection Devices: some alternators are equipped with thermal sensors or protection devices that shut down the alternator if it reaches a specific temperature, preventing damage from overheating.

internal Voltage Regulators: The voltage regulator helps maintain the alternator's output voltage, preventing excessive current flow, which can lead to overheating. By regulating the voltage, it helps ensure the alternator operates within safe limits.

Proper Installation and Maintenance: Ensuring that the alternator is correctly installed and regularly maintained can help prevent overheating. This includes checking for loose connections, worn-out bearings, and ensuring that the drive belt is not too tight or too loose.

Adequate Charging System: The overall health of the vehicle’s charging system, including the battery and wiring, can impact alternator performance. A failing battery or corroded connections can cause the alternator to work harder, leading to possible overheating.

Cooling Systems: In some vehicles, the alternator may receive cooling assistance from the vehicle's overall cooling system, especially in high-performance applications.

Regular inspections and maintenance can help prevent overheating and extend the life of the alternator.

[CaptainRivet]

Originally Posted by Chaff

So what protects the alternator from overheating if u just chuck in an argofet?

The 115A Mitsubishi and the 125A Valeo found stock on all newish, means with serpentine belt, Volvo, Yanmars, Betas, Vetus.....have already a very well working and actually conservative internal temp protection that regulates internally so the alternator does not overheat.
That is even better then the externally regulated alternators as the temp sensors sits internally very close to the stator where the most heat is created and situated so regulation is even better!!!
Their regulator (for all the marine engines and most trucks, just check whichbregulator is mounted) is an agm one that delivers between 14.2 and 14.4 and is not exceeding 14.6V so perfect for lithium too.

these 2 alternators where developed for commercial small cooling trucks in hot climate in the 3rd world means these trucks need a lot of current while just standing and eg loaded or discharged. So they need to rely on their own self cooling capability as no driving wind and they need to be temp controlled to always deliver the maximum their internal temp allows continuously as the temps change drastically in these areas as they can be 10 degrees at night and 45 during day. Additionally these trucks have dual purpose big agm batteries that have an internal resistance that's close to lithium. Due to this they have proper heavy duty avalanche diodes that also survive a sudden disconnect. Made for the worst environment...
I know this all because I was the responsible overall for reorganizing Mitsubishi worldwide (especially the aftersales and product development) after Mercedes bought Mitsubishi/Fuso trucks and I have access to all the technical documentation.
Their is no better bang for the buck then a remanufactured 115A Mitsubishi alternator that's around 250Euro, reman because the aftermarket don't have the internal temp control and the heavy duty avalanche diodes which makes the alternator so good.
So via argofet, the starter lead protects the installation from a sudden disconnect spike by absorbing it while the alternator can perfectly care about itself and always deliver max it's internal temp allow.
If you wanna optimize that you can get the Nordkyn VSR200 modul that without modifying the alternator can regulate it externally and maximize output as internal temp control is very conservative and in a lot of well ventilated vessels, eg a lot cats like mine too, you can run it longer on higher current levels and therefor a bit hotter. Also one VSR200 can regulate up to 4 alternators on one engine...2x 115A deliver 170A constant, if you modify gearing to 3.3:1 you even get real regulated 200A constant and 150A from 1300RPM on. That's 500Euro for the alternators, make the brackets yourself and you get 170A for 600Euro regulated and temp protected, add the Nordkyn for 350Euro and you have also an external regulated solution that won't void the manufacturer engine warranty as 2 original alternators on one engine is covered and you don't modify the existing install, you just add the 2nd OEM alternator. Plus compared to one big heavy duty alternator you have redundancy and practically a "working spare". The 2nd alternator sits mostly on the top part with better ventilation then original position so has typically less wear and tear as heat is the most failure source on these alternators.

[CaptainRivet]

All engines where the 115A Mitsubishi or the 125A valeo is stock meant the small 3 and 4 cylinders and some 6 cylinders with serpentine belt drive.
The 125A valeo on Betas are optional and need a special connection cable as the stock cable missing a connection and disabled the temp control via cable.
On all this cases a DC2DC is a waste of money and additionally castrate the alternator of its abilities.
The only 2 changes you need to make with a argofet because the battery positive runs originally to alternator and then from alternator to starter.
1) You have to disconnect the connection starter to alternator. Then run a sufficient cable (most cases a 35 or 50sqmm is appropriate) from starter directly to starter battery, you can integrate a fuse or in this case I highly recommend a breaker suited for motor loads if you wanna fuse that connection to make things perfect and sleep better, you don't have to.
2) you disconnect the positive and negative cable from alternator at the starter battery and in positive add fuse or breaker speced for lower rating of cable or the 200A rating of the argofet. The fuse ouput connect it to the argofet. Then connect out 1 to starter and out 2 to a disconnect device like an SSR (preffered as not mechnical, the argofet protects it from reverse current and spikes) or a relay that either your last resolution desaster cut off or the BMS steers.
I use here
A) preferable the BMS that steers the SSR/relay if it has additonal steering like my eletrodacus BMS can switch on/off sources based on SOC threshold, eg rec BMS can do this too. Also if you have a victron cerbo GX installation you can use one of its relay steering outputs to disconnect the alternator at 13.5V and switch on if below. A small relay in the sense wire to alternator is enough, you Don't need to disconnect the high current path. This switches off the field wire and alternator delivers no current. I can case of an internal failure eg short of alternator the fuse will blow and complete disconnect the alternator.
B) if dropin or no external steering BMS I use here the Easy as alternator relay that only enables the connection when the alternator is running, it's doing that via its sense wire that scans for typical ripple that only an alternator creates and that doesn't get fouled by other charge sources as all the Victrons devices do that are regulated by voltage. The easy as relay is also a voltage sensing relay at the same time so it can disconnect itself the alternator connection when the 13.5V of the LFP is reached or below 10V and disconnects the alternator before the BMS disconnects.