My new to me 30C has 5 lead acid batteries (1 start 4 house) likely all dead as they have been sitting for a good while. Anyway I want to convert to a hybrid system with a lead acid starter and lithium house. I’m fishing for ideas from anyone who has gone this route. Thanks!
You might want to take a look at Eric Larsen’s post in the discussion just a few days ago in the discussion titled, “Battery under aft starboard berth”:
https://groups.google.com/g/INA-Nonsuch-Discussion-Group/c/W5lGUP_JBR4
Note how we encourage people to sign with names and boat information to raise the chances of getting responses that best fit their situation. It works both ways. You might get good local advice if folks know where your boat is, and I would’ve had a lot of trouble explaining which post you should look for if Eric hadn’t signed his post.
– Bob
Me Gusta
Nonsuch e26U #233
Looking forward to seeing folks in Toronto:
https://nonsuch.org/2024-INA-International-Rendezvous-Status
Bob thanks! I did look at the Eric Larsen post. I would like to avoid the bank manager solution. I think something simpler will do fine. Just thought someone in the INA might have a simple hybrid setup.
Roger
Tranquility
30C 240 Port Aransas TX
The fundamental issue to be resolved is the different charging profile of lithium compared to lead acid batteries. There are several ways to resolve this issue, but it is not a simple drop-in replacement. If you have solar panels you can easily charge the lithium with a proper solar charge regulator. Be warned however that you should probably make sure you purchase LiFePo4 chemistry with a reliable BMS to avoid a potential fire. Be wary of what appear to be bargain priced batteries as there are many substandard manufacturers.
Ron Weber,
N22 Magic Time
Punta Gorda Fl
Roger,
I replaced my (2) flooded lead acid house batteries last season . I considered lithium LFP and flooded Pb-Acid and AGM Pb-Acid for cost, install effort, etc. Attached is a matrix evaluation I did that you may find helpful. The INA website also has a helpful “Batteries 101 document”. I ended up deciding to replace the house batteries with AGM and replacing the original AC charger. One consideration with LFP is that addition equipment is needed to protect the engine alternator from the high charge currents the LFPs can draw.
(attachments)
Battery options.xlsx (20.2 KB)
Lots of info on the subject here..
For me the equation was how much battery storage do I need. I went with 4 group 31 AGM batteries for my house bank. I spend all season on moorings. With the money I saved from not buying LI batteries and everything that goes with them. I bought 200 watts of solar panels , all the wiring and a MPPT charger controller. I still came out way ahead on price and have plenty of power.
Peter Farley
Knot in a hurry u30 #328
Keyport nj
I am surprised to hear this. When I was replacing AGM with LiFePO4, the cost savings was greatly in favor of going with lithium. My single 300ah (which has 300ah usable) LiFePO4 battery cost less than 4) 100ah AGM batteries (having only 200ah usable) and weighs about 1/3 of those 4 AGMs. When you analyze by amp-hours per dollar, it’s not even close ($2.50/AH vs $4/AH – calculated at $200 per AGM battery if you can even find $200 AGM GR31 batteries). You don’t have to buy new chargers with lithium when in a hybrid array so no cost there. You do have to put about $400 into a hybrid controller, and possibly go to an externally-regulated alternator, though.
Eric Larsen
S/V Felix 1981 30C #115
Olympia, WA
Well I don’t know, you managed to do it with a lot less changes than I was told to make. I contacted these folks to review what I had and what I would need to change. https://battlebornbatteries.com/using-lithium-batteries-in-sailboat-electrical-systems/. They said the standard 55 amp alternator was really too small for the new battery based on the fact I would not be able to charge that battery as quickly as the battery is capable of. The said I could maybe get away with an external regulator that talked to the BMS but the did not recommend that. It would basically keep turning off the alternator as it overheated. Using a dc to dc charger limits the speed and capacity of the charging to the lead battery. They recommended I get the Balmar 100 amp alternator with the external regulator that talked to their BMS. That then used the wider belt so all the pulleys would have to be changed as well. They also said my shore power battery charger would need to be changed. Plus all of the wiring changed that go along with this.
Peter Farley
Knot in a hurry 86 u328
Keyport NJ
I don’t have LIi. But I have a 120 amp alternator and a Balmar regulator. I charge wet cells , two golf cart and a start. Since they won’t accept much more than 50 amps 80% of the time I dial down the alternator to a max of 80 amps using settings in the regulator. This enables me to stick with the standard 1/2" v belt. Using the 80 amps as the max I then wired the alternator to the battery with a 125 amp fuse and switch.
So could you not get the 100 amp Balmar/Regulator and dial it back to 80 amps, stick with the current belt system. It would be running at 80 amps most of the time.
One thing I did was change the wiring from Battery-switch-alternator-starter. I now have Alternator - alternator switch-fuse-house battery. And Battery-main switch-starter.. So the circuits are seperated.
I find the starter is happier and the battery is now fully fused to all loads.