Thoughts on LIFEPO4 Plan

[Letterkenny]

Originally Posted by s/v Jedi

That is exactly what I have. You need the Orion Smart non-isolated, assuming your DC negative is connected to the engine block and your house battery negative is connected to start battery negative (like most boats)

But for two of these Orions which do 30A each, you need a very beefy alternator. Any standard alternator under 120A will overheat and fail shortly after installing this. In this case you should use just one of the Orion’s and measure temperature to make sure it doesn’t overheat. In the Orion setup you can further limit the current if needed.

For my two Orion’s plus two start batteries, I have a Balmar 170A alternator with temperature sensor that is connected to the smart regulator which will limit output when temperature gets too high. This doesn’t happen because it can handle it, but it still gets toasty

Thanks for that. Sounds like I’d be limited to the 30a then but results in pretty low input into the batteries. Will need to think if it’s better to use these vs the AGM and run to a lower DOD. Read some studies there and it doesn’t sound like the worse thing in the world for lifespan but the cheaper LIFEPO4 are certainly an attractive solution.

[emilecantin]

Originally Posted by s/v Jedi

If you want to directly charge a LFP bank from the alternator at high charge rates, you must replace the oem alternator with a much larger unit that has a smart external regulator incl. temperature sensor on the alternator

Sorry, that's what I meant by "high-output alternator", sorry if I wasn't clear.

I actually already have such an alternator, however I suspect it's pretty limited in terms of amps it puts out because
1- I only ever see about 30-35 amps coming into the battery, max and
2 - the previous owner gave me some parts saying something about upgrading the pulley on the alternator, a project he didn't have time to finish.

Now that I've gone into the Balmar rabbit hole, I know their regulators have something called "belt load manager", and mine is probably heavily throttled.

[PaulCrawhorn]

An alt can be whatever size & type

so long as converted to use an external current limiting VR

that will protect as well as a DCDC.

The amps don't NEED to be automatically scaled up and down real time based on temp sensing.

So long as you are conservative, that adjustment can just be a seasonal thing done manually.

[s/v Jedi]

Originally Posted by PaulCrawhorn

An alt can be whatever size & type

so long as converted to use an external current limiting VR

that will protect as well as a DCDC.

The amps don't NEED to be automatically scaled up and down real time based on temp sensing.

So long as you are conservative, that adjustment can just be a seasonal thing done manually.

For charging LFP? I am not aware of any regulators that can charge LFP but don’t support a temperature sensor on the alternator?

[hjohnson]

Originally Posted by emilecantin

I'm going to do the exact same in the next few days (Orion feeding from starter battery); glad to hear it works well.

However, in theory you're losing a golden opportunity by wiring your alternator to the starting bank. The best way to take full advantage of a high-output alternator is by plugging it into the largest bank you have on board, and only when that one is full should you charge the other banks. The larger bank can probably accept the full alternator's output, whereas the small one probably can't. The situation is similar with shore power.

That’s exactly what I’m doing as well, and it works beautifully. I had an 85A Hitachi alternator modified for external regulation by a local alternator shop, and then grafted it onto my poor little Yanmar 1GM10. The alternator is controlled by a Wakespeed regulator, which is under full control of my BMS.

I then use an 18A Orion Tr to maintain the starter battery (cheap Marine start fla).

Having integrated power is fantastic; everything works together and communicates, and it’s all controlled by the battery. Inverter/Charger, solar MPPTs, alternator. It’sall managed as a system, and can all be monitored remotely. It’s glorious and worth every penny, imho.

Plus, I can now remotely check in on my instrumentation to see if there’s enough wind to bother going out sailing.

[CaptainRivet]

Originally Posted by Letterkenny

Thanks for that. Sounds like I’d be limited to the 30a then but results in pretty low input into the batteries. Will need to think if it’s better to use these vs the AGM and run to a lower DOD. Read some studies there and it doesn’t sound like the worse thing in the world for lifespan but the cheaper LIFEPO4 are certainly an attractive solution.

Solar is your best friend here, cheap and if you use bifacial panels you get a lot per SQM and is your main charge source. The alternator has to simply work, so 30A is ok and not burn through when you motorsail with lithium. If it’s older and need replacing soon, I would install a high output alternator with external regulator to charge the LFP directly.
Lithium is the much better choice which charges much faster then AGM and much safer. I was tossing myself an AGM overboard that ran dry because of a faulty regulator and got a thermal runaway. The same happened with my new BMW, alternator was ok but battery faulty and I was ripping out the runaway AGM on a highway parking before the car started burning. The gassing was horrible, thanks good I had by luck a proper 3M painting mask in the car, without that won’t have been possible to it rip out.Both where expensive Varta quality batteries…
I prefer Lithium but I am ok with FLA that you can refill, the Optimas and good gel but an AGM will be never again in a boat I own.

[s/v Jedi]

Originally Posted by Letterkenny

Thanks for that. Sounds like I’d be limited to the 30a then but results in pretty low input into the batteries. Will need to think if it’s better to use these vs the AGM and run to a lower DOD. Read some studies there and it doesn’t sound like the worse thing in the world for lifespan but the cheaper LIFEPO4 are certainly an attractive solution.

I don’t understand this. The “low input” is caused by the alternator overheating with larger output, not by which battery is used.

If you want high power then you can’t use the oem alternator.

[CaptainRivet]

Originally Posted by hjohnson

That’s exactly what I’m doing as well, and it works beautifully. I had an 85A Hitachi alternator modified for external regulation by a local alternator shop, and then grafted it onto my poor little Yanmar 1GM10. The alternator is controlled by a Wakespeed regulator, which is under full control of my BMS.

I then use an 18A Orion Tr to maintain the starter battery (cheap Marine start fla).

Having integrated power is fantastic; everything works together and communicates, and it’s all controlled by the battery. Inverter/Charger, solar MPPTs, alternator. It’sall managed as a system, and can all be monitored remotely. It’s glorious and worth every penny, imho.

Plus, I can now remotely check in on my instrumentation to see if there’s enough wind to bother going out sailing.

A 600$ wakespeed on a 85A Hitachi alt that maybe deliver 40A constant plus costs modifying it doesn‘t really make sense…a 30A DC to DC is a much cheaper and better choice plus that makes sure the starter is always full, your expensive solution not.

[goboatingnow]

Originally Posted by CaptainRivet

Solar is your best friend here, cheap and if you use bifacial panels you get a lot per SQM and is your main charge source. The alternator has to simply work, so 30A is ok and not burn through when you motorsail with lithium. If it’s older and need replacing soon, I would install a high output alternator with external regulator to charge the LFP directly.
Lithium is the much better choice which charges much faster then AGM and much safer. I was tossing myself an AGM overboard that ran dry because of a faulty regulator and got a thermal runaway. The same happened with my new BMW, alternator was ok but battery faulty and I was ripping out the runaway AGM on a highway parking before the car started burning. The gassing was horrible, thanks good I had by luck a proper 3M painting mask in the car, without that won’t have been possible to it rip out.Both where expensive Varta quality batteries…
I prefer Lithium but I am ok with FLA that you can refill, the Optimas and good gel but an AGM will be never again in a boat I own.

Good the best place for AGM is the bottom of the ocean utterly oversold technology out of place on a boat

[CaptainRivet]

Originally Posted by s/v Jedi

I don’t understand this. The “low input” is caused by the alternator overheating with larger output, not by which battery is used.

If you want high power then you can’t use the oem alternator.

He thinks the LFP are not worth putting in because of the low input from stock alternator+ DC2DC charger and instead would use AGM.

[s/v Jedi]

Originally Posted by CaptainRivet

He thinks the LFP are not worth putting in because of the low input from stock alternator+ DC2DC charger and instead would use AGM.

Yes, I think so as well, but it doesn’t make any sense. I hurts to see so much money and effort wasted on senseless installations

[macieknan]

200 amp Yandina combiner is under 150 bucks and could simplify the setup and reduce the cost. While you are at it you could also get their galvanic isolator for your shore power connection as well

[hjohnson]

Originally Posted by CaptainRivet

A 600$ wakespeed on a 85A Hitachi alt that maybe deliver 40A constant plus costs modifying it doesn‘t really make sense…a 30A DC to DC is a much cheaper and better choice plus that makes sure the starter is always full, your expensive solution not.

Maybe the guy who rebuilt it did some magic (he did replace the rectifier with an oversized one), or maybe the airflow is particularly good (there’s nothing behind the alternator to impede airflow) but I can pull a continuous 70A out of it, and it tops out at 75C (confirmed with an IR thermometer).

The main reason why I went this route was to be able to manage the lead on the engine. I have the WS500 configured to run at virtually no load when the engine is below 1000rpm, so when I’m putt-putting back into my slip there’s no drag on the engine (much more responsive to throttle inputs than the oem alternator). It then ramps up slowly as I go towards cruising rpms.

It’s basically what has made having a comparatively large alternator practcal on an engine that’s powered by a geriatric squirrel with a bum leg.

[CaptainRivet]

Originally Posted by hjohnson

Maybe the guy who rebuilt it did some magic (he did replace the rectifier with an oversized one), or maybe the airflow is particularly good (there’s nothing behind the alternator to impede airflow) but I can pull a continuous 70A out of it, and it tops out at 75C (confirmed with an IR thermometer).

The main reason why I went this route was to be able to manage the lead on the engine. I have the WS500 configured to run at virtually no load when the engine is below 1000rpm, so when I’m putt-putting back into my slip there’s no drag on the engine (much more responsive to throttle inputs than the oem alternator). It then ramps up slowly as I go towards cruising rpms.

It’s basically what has made having a comparatively large alternator practcal on an engine that’s powered by a geriatric squirrel with a bum leg.

Ok that makes sense overall, still expensive but definitely works for your setup.
Wows that’s magic, a 85A alt delivering 70A continuous…can you please tell us the exact model or order number if an OEM one. If he didn‘t relocate the rectifier away from the alternator then that could make out of 40A maybe 50A but not 70A.

I already have one of the best stock alternators, the 115A Mitsubishi that even has a quite conservative temp regulation and that can deliver 80A for about 15min before throttling back to around 60A.

[hjohnson]

Originally Posted by CaptainRivet

Wows that’s magic, a 85A alt delivering 70A continuous…can you please tell us the exact model or order number if an OEM one. If he didn‘t relocate the rectifier away from the alternator then that could make out of 40A maybe 50A but not 70A.

I already have one of the best stock alternators, the 115A Mitsubishi that even has a quite conservative temp regulation and that can deliver 80A for about 15min before throttling back to around 60A.

It’s just an isolated ground hitachi alternator that was oem on a 4 cylinder Yanmar. We inherited it after it was replaced with a balmar.

When I had it modified for external regulation, the guy at the alternator shop replaced the bearings, and put in a diode pack that would normally be used on a 120A alternator.

The other thing that really helps is that it is mounted to a 1GM10, which has nothing behind where the alternator goes, as it’s a raw water cooled engine, so no heat exchanger, and no exhaust manifold due to being a single cylinder. This, the alternator can ingest as much cooling air as it wants. I have the temperature probe from the Wakespeed bolted solidly to the rear of the alternator, and never seen it go above about 75C.