Starter Batteries vs House Batteries on My Boat

[@giovannifiorentino8947]

I can never get enough of boat battery topic.

[@PacificYachtSystems]

Same here.

[@haydensmith2289]

Thanks Jeff! If you mention an hour long geek session or article, you could add it as a link in the description, in the corner or at the end of the vid. Lead us down the rabbit hole!

[@PacificYachtSystems]

Fantastic! You could start with the "How To: Marine Electrical Seminar". Episode 2 (of 29) is all about batteries. www.pysystems.ca/resources/videos/

[@thekiteboatparty3568]

You can geek out on Jeffs videos for hrs, while my friends have been binging Netflix during Aucklands latest lockdown, Jeff has taught me all the mistakes I made wiring my old kite boat. If you really want to go hundies start reading/watching up on lithium conversions, now that is a minefield. I wish Jeff was here in NZ so i could just pay his guys to come instal it for me.

[@stevecarter9027]

I have long wondered about starter batteries, so on my last boat I just used 8 golf carts , and had no dedicated starting batteries. (Twin 60 hp outboards) As a test, I let the voltage get down to 11 volts (one battery set only) and the engines started just fine. Why have all that starting ampactity not be part of the house??? New boat, new batteries on twin diesels, I think I want a big house only set, with perhaps one of the house set, that can be electronically disconnected, at a pre determined voltage. We never had a problem starting without dedicated start batteries, and had a start jump pack in case we ever did. One set of batteries made the install and switching so simple!

[@rogeremeadowsyahoocom]

Jeff, great video. May I ask the typical life of a house bank battery...12V 150 ah AGMs..

[@wadebarrie1433]

Is there any issue running your windlass of your start battery as long as you always have your engine running when operating the windlass?

[@robintaylor1490]

Thanks Jeff 😉, boat has been delayed twice which is expected given our present day circumstances. 🙄 Hopefully it'll be ready for the boat show in February 🤷‍♂️

[@PacificYachtSystems]

We'll be ready when your boat is... hopefully sooner rather then later.

[@j-rock1344]

So if I'm running my boat of the starter battery how would my dept finder work if it's hooked to the house battery side, another words using accessories while the boat is in motion

[@j-rock1344]

While using a battery switch.

[@rmcnabb]

Great info, thanks so much. I just bought a sailboat with 2 new marine deep cycle batteries (identical) that are split between charging and house duties. Can I combine these 2 into the house bank, and add a dedicated starter battery? One bank would the starter batt, the other bank would be the two house batts. Thanks!

[@PacificYachtSystems]

Yep, you can definitely put two similar batteries in permanent parallel to run your house and a separate engine battery

[@thekiteboatparty3568]

Thanks Jeff, this was a very topical video for me because i’m looking to replace my lead acid house batt with a LiFePO4 + DCDC charger drawing off the start batt. I’m wondering though, as the solar will just be charging the new house batt. Is there a good way to somehow trickle charge the start batt from the solar as well since with my new configuration it will only be being charged from the alternator… Could it be as simple as connecting my solar charger direct to my start batt instead of the house batt? 🔋 🔌 ⚡️

[@PacificYachtSystems]

Your on the right track, easiest is probably having your solar array controller connected to engine instead of house battery. Anyone else have suggestions on how to do this.

[@thekiteboatparty3568]

@@PacificYachtSystems Thanks for the reply Jeff! Yes, that was my plan too but last night i saw this short video and it changed my mind. kzbin.info/www/bejne/qHW7mqt5r8xpn9k My existing votronic charger can trickle the start batt at a voltage that i can set the victron dcdc to not quite start at so that it will only charge the lithium house off the alternator when the alternator is suppling enough current to not let the start batt get depleted. I can run the main solar feed to the house batt too. But now my big question is what size dcdc to get to prevent my alternator overheating and not deplete my start batt while the voltage is high from the alternator like in this video.

[@dannyjensen4954]

The Kite Boat Party Thanks for the video link. I charge my house batt and have a ACR trickle charge the starter. I have rigged a trigger enable to turn off the charger. Good chargers have a voltage sense wire. My dc dc will only draw down my batt for a few minutes after a charge. Here is my discovery on the voltage sense wire kzbin.info/www/bejne/rJnUh4qJatylm5I .

[@teachingrounds]

Jeff love your stuff but it’s time you should venture a little and start, first trying, and then talking about lithium. It’s a game changer

[@PacificYachtSystems]

Thanks for the encouragement. As we get to see and tackle more and more installs, we are uncovering the unknowns. Over time, we'll share it with everyone.

[@thekiteboatparty3568]

@@PacificYachtSystems fair enough but it would still be cool to see more lithium videos, you already alerted us to the dangers of a dead BMS but that can be mitigated a bit by having a switch to divert essential house loads to the start bank in emergencies and/or by having a low voltage alarm and monitoring your battery monitor closely. For me the main reasons i want to do it are ease of physical battery install and more than twice the usable capacity in the same limited space. Those are very good reasons i feel many can relate too. Finally if all goes dead you always have your sails (or kite if you are a kite boat). The only Fireflies Captain Cook needed were the ones “that, uh… got stuck up on that big bluish-black thing” - Timon

[@jb7702]

Hello Jeff. What's your opinion on the "dual purpose" (high cranking amps and deep cycle) lead acid batteries? My boat's PO installed two deep cycle batteries for starter and house loads. I want to install a dedicated starter battery. Is the dual purpose a viable option?

[@PacificYachtSystems]

Good question, would recommend getting a starter battery for your engine and deep cycle battery for your house loads. Deep cycle batteries aren't as good as starting batteries for engine starting.

[@jb7702]

@@PacificYachtSystems I may not have been clear. There are flooded lead acid batteries that are labeled as dual purpose, meaning they can supply the high cranking amps for starting, and also sustain deep cycling. Do they live up to their claims?

[@ronnybohl-vaz6860]

Hi Jeff. I have a 31fot alicraft and have been refurbished almost everything on it now I’m doing al my electrical on my boat and I’m at changing my battery bank’s. I’m using 2 optima red top batteries for start one for each engine with a crossover switch just if one of them runs out of power. And I have an 12V 155Ah Front Terminal AGM VRLA Battery from MonBat that I’m using for house battery. How do you recommend the charging setup for this do I need a dc to dc charger or just a charging really from each engine battery bank to house battery? Best regards Ronny from Norway.

[@PacificYachtSystems]

Hi Ronny, DC to DC charging converters are great, as you can customize the charge output.

[@ronnybohl-vaz6860]

@@PacificYachtSystems tanks for The for your answer. I was thinking abaut a dc to dc charger

[@javierbetancourt9388]

💯

[@PacificYachtSystems]

Thanks Javier!

[@traviscrawford1445]

Great information as always! I have a quick off the topic question. Surge protection devices. Can I use an all house hardwired device in a boat? The one I have is a D square 120V/220V single phase 3 wire. Thanks Jeff!

[@alcibiadesmarcialneto922]

Knowing that spacecraft and flying vehicles are not grounded, why do US standards require this? I was told that in Europe this is prohibited. Thanks.

[@PacificYachtSystems]

Good question, but not sure of the why the code is the way it is. To me, one of the benefits of having a reference voltage, i.e. ground, provides a good way to interconnect different AC and DC voltages.

[@alcibiadesmarcialneto922]

@@PacificYachtSystems thanks for your answering. All power plants and substations use unearthed DC. This is to protect it from electrical surges due switching and lightning. Combining them will transfer the issues from one place to other with undesired effects.

[@ashtongrist]

I dont even know if we are talking about lithium or not