Battery question concerning audio set up for a newbie

[Jmesduncan]

First off I want to say I’m a literal newb in every aspect of batteries and boating. I’ve got two summers under my belt owning a boat and living on a lake. With that said I have a 2007 Caravelle 210. I am adding a pretty extensive sound system in it this off season. I will have two 12 inch subs in an enclosure and 6 total 6.5s with leds. Two amps one 1500 watt x1 class d and one 1000 watt x4. So my obvious (annoying to some I’m sure) question is….
My boat currently has one crappy battery. Can’t tell you what it is but it’s def coming out. I know I need more battery for this set up. My questions are what batteries and how is this done being I have only one battery set up and not one cranking battery and one house power one. Also I leave my boat in the water pretty much the whole season and there’s no power I believe out there. Could be but I’m not sure on that. So obviously I’d assume the boat has an alternator so it would charge in some fashion but I’ll probably need to plug up I’m sure which I can do I will just pull it to the house. I’m wanting to be comfortable being able to play at high volume if wanted for 2-6 hours without dropping off. Also wonder how the batteries charge.. will my boat charge them while riding?? First off thank you anyone who read this and I know I’m going to have someone say do some research. The issue is I’m extremely busy I don’t know what I’m really looking for and also I think the purpose and benefit of forums is to share knowledge to save someone from having to spend hours googling stuff because someone already has done that. Thanks again.

 

[FSH 210 Sport]

First off I want to say I’m a literal newb in every aspect of batteries and boating. I’ve got two summers under my belt owning a boat and living on a lake. With that said I have a 2007 Caravelle 210. I am adding a pretty extensive sound system in it this off season. I will have two 12 inch subs in an enclosure and 6 total 6.5s with leds. Two amps one 1500 watt x1 class d and one 1000 watt x4. So my obvious (annoying to some I’m sure) question is….
My boat currently has one crappy battery. Can’t tell you what it is but it’s def coming out. I know I need more battery for this set up. My questions are what batteries and how is this done being I have only one battery set up and not one cranking battery and one house power one. Also I leave my boat in the water pretty much the whole season and there’s no power I believe out there. Could be but I’m not sure on that. So obviously I’d assume the boat has an alternator so it would charge in some fashion but I’ll probably need to plug up I’m sure which I can do I will just pull it to the house. I’m wanting to be comfortable being able to play at high volume if wanted for 2-6 hours without dropping off. Also wonder how the batteries charge.. will my boat charge them while riding?? First off thank you anyone who read this and I know I’m going to have someone say do some research. The issue is I’m extremely busy I don’t know what I’m really looking for and also I think the purpose and benefit of forums is to share knowledge to save someone from having to spend hours googling stuff because someone already has done that. Thanks again.

Tell us a bit more about your boat and mainly it’s power plant. When I searched for your boat I got everything from outboards center consoles to bow rider I/O’s. It might also be helpful to post pictures.

There are lots of threads here where people have added dedicated house batteries while keeping the start battery isolated when the engines are off. I’m sure we can get you linked to those threads which will cut down your research time. Basically the system adds a voltage sensing relay that closes a switch when the engine(s) are running so that both the start and house batteries charge, when the engines are off the voltage sensing relay opens the switch and only the house battery is connected to load so the start battery is fully charged and is only used for engine starting.

Your boat has an alternator…otherwise you’d have a dead start battery .. so it will charge your house battery as well. But that charging is highly variable depending the charging system that is on your boat and how long the engine is run. An on board battery charger that can be plugged in should be part of the upgraded battery project as well, that makes it much easier to re charge your batteries and or keeping them charged for the next outing.

 

[Jmesduncan]

I apologize and thank you for the response. It has a 5.0 V8 Volvo penta I/O. Yeah I know it has an alternator but I’m wanting to know if that alternator could recharge the extra large batteries. I know I need a dual battery switch and two batteries. So what’s the best options for the batteries with potentially 3000 watt rms audio set up plus some leds. Any other questions I will do my best. I’m going to try to attach a pic. ANY HELP OR SUGGESTIONS would be greatly appreciated. Like I said before I’m starting from scratch here and have to learn a lot and also learn what all people suggest speaker wise. As of right now I’m planning on clarion 6.5s that are 80 watt rms. These have built in leds. Running 6 of those and two 800watt rms Skar audio svr 12s in a ported box. I know they are not marine but I have a spot that’s water tight with exhaust and all so moisture shouldn’t be a problem. The amps will be Skar marine 1500 class d and 1000 class a/b.

 

[Jmesduncan]

Tell us a bit more about your boat and mainly it’s power plant. When I searched for your boat I got everything from outboards center consoles to bow rider I/O’s. It might also be helpful to post pictures.

There are lots of threads here where people have added dedicated house batteries while keeping the start battery isolated when the engines are off. I’m sure we can get you linked to those threads which will cut down your research time. Basically the system adds a voltage sensing relay that closes a switch when the engine(s) are running so that both the start and house batteries charge, when the engines are off the voltage sensing relay opens the switch and only the house battery is connected to load so the start battery is fully charged and is only used for engine starting.

Your boat has an alternator…otherwise you’d have a dead start battery .. so it will charge your house battery as well. But that charging is highly variable depending the charging system that is on your boat and how long the engine is run. An on board battery charger that can be plugged in should be part of the upgraded battery project as well, that makes it much easier to re charge your batteries and or keeping them charged for the next outing.

I’m such a dummie I put Caravelle 210 it’s a 207. I applying have no idea where that came from.

 

[FSH 210 Sport]

No worries!

I’d like a close up pic of the silver label that is on your alternator, it should have the specifications on it.

I am sure that alternator can recharge your batteries. Once I have the specs I should be able to tell you how much charge capacity you will have.

Once I have the alternator capacity I’ll give you a couple of options on set ups for batteries, isolaters etc.

 

[Jmesduncan]

Man I appreciate your help. I will get those pics as soon as I get to the house this evening.

 

[Jmesduncan]

Is this what you were needing? I’m pretty sure it says 65 amp. Whatever that determines.

 

[FSH 210 Sport]

Yes, that’s what I need. I can see it but a clearer picture would be great.

65A is full output, continuous is bit lower I think. I’ll check with my friend and see what he says about the duty cycle. Just guessing at a 80% duty cycle that’s roughly 50A, pretty significant, that should be more than sufficient for what you want to do.

 

[FSH 210 Sport]

I spoke with my friend earlier and he said the Volvo alternator ratings are 100% duty cycle, so that’s great.

As far as batteries go, if you are going to stay with lead acid chemistry, and want the lowest cost per kWh / Ah then go with your basic RV / Marine deep cycle flooded lead acid batteries. Group 24 batteries are roughly $150 each. These type of batteries will drop right into your system with the addition of switches and a vsr type of isolater.
The lowest cost per KWh over the long run are LiFePO4 batteries. These batteries have a high initial cost, $700-$1000 each but have twice the KWh / Ah and half the weight for the same size battery but will last about 5 times as long. They will require a DC to DC on board charger to protect your boats alternator. This may be the simplest way to go for you as with this set up you may not need the vsr, I’ll have to investigate a bit further on that.

So what kind of budget do you have for this project? That will determine the course from here.

 

[Jmesduncan]

thank you so much!! I’d like to stay about $300 per battery.

 

[FSH 210 Sport]

Alright.. you should be able to do both your batteries for around $300…

How much room do you have for mounting another battery? Is there space for another battery of the same size where your start battery is? Several of the guys here mounted their switches etc on a piece of starboard and then mounted that in the hood where the batteries are. You may want to look around for somewhere to mount all that stuff.

 

[Jmesduncan]

Yea I do have enough room for another battery next to my existing one. I have a spot picked out for switches also next to them. So I’m looking at some agm batteries but I’m wondering what amp hours and all I should be looking for.

 

[FSH 210 Sport]

Yea I do have enough room for another battery next to my existing one. I have a spot picked out for switches also next to them. So I’m looking at some agm batteries but I’m wondering what amp hours and all I should be looking for.

Measure the area where the batteries are going to go and make sure you have enough room to mount the battery size you want. The marine master battery that’s in there now are good batteries that are made here in the U.S.A. I used them for my trolling motor before I switched over to LiFePO4 batteries. Below is a link to their batteries with all the specs.

https://www.eastpennmanufacturing.com/wp-content/uploads/0007-DEKA-SLI-Spec-Sheet.pdf

Basically, a group 24 will give you 75Ah, a group 27 battery will give you about 90Ah, and a group 31 will give you about 100-105Ah, but keep in mind that the useable Ah in any lead acid battery is about 40-45% of their rating. That’s because if you draw the battery down lower than that it’s life cycle is reduced greatly.

It is very important that you have a good on board charger with at least 10A of charging capacity per battery and that the batteries be put on the charger as soon as possible after an outing to prevent the plates from sulphating. Sulphating occurs when a lead acid battery sits in a partial state of charge. Victron Energy makes a couple of different chargers that have Bluetooth connectivity where with the downloadable app you can see what the charger is doing in terms of where it is at in the charge cycle, volts, and amps. I recently installed these chargers for my trolling motor batteries and they work great. I believe the chargers I installed are the IP 67 model, these chargers have a choice between 10A or 25A of charging current, are selectable for any type of battery, and if you go with the flooded acid type of battery there is a reconditioning cycle (equalizing charge) that will keep the batteries at peak performance and give the longest life out of your batteries. This charger is water proof and ignition sealed.

https://www.victronenergy.com/chargers/blue-smart-ip67-charger-waterproof

The AGM batteries are a good choice as they are sealed. However, the best bang for your buck will be the flooded lead acid type, either way the batteries should be in their own separate battery boxes if possible.

Here’s the OEM battery switch that comes with the Yamaha boats with two batteries, the DVSR and auto charging built in. I like it as it is compact and clean.



And here’s the single line drawing. Operation: Turn on the start and house switches and you are ready to rock. Once you start the engine the alternator starts charging the start battery, when the voltage on the start battery comes up to 13.2 volts the DVSR closes the switch and parallels the start and house battery and the house battery starts charging off of your alternator as well. Once you stop and turn off the engine, the start and house batteries stay in parallel until the voltage drops to 12.7, then the DVSR opens the switch breaking parallel between the start and house batteries. Your start battery is now isolated from all accessory loads and will be ready to start the engine, even if you run the house battery all the way down. At this point all your accessory loads are coming off of your house battery.



Blue sea makes a similar type of charging relay. Both of these systems will prevent your electronics from being exposed to starting voltage transients from getting to your sensitive electronics as the DVSR / VSR relays will open the switch between the batteries when then starter motor engages.

You should also install a battery monitor if you don’t already have one. I installed a Victron Energy Bluetooth shunt on my trolling motor battery bank and I will be installing another one on my house bank. This device will also monitor your start battery voltage as well. The shunt will measure the voltage of your house battery, how many KWh / Ah your battery has used, and display the state of charge of your house battery. Without this type of monitoring device, determining the state of charge of your house battery is just a guess. The Bluetooth shunt is read by a downloaded app on your smart device and is configurable to any type of battery.

https://www.victronenergy.com/upload/documents/Datasheet-SmartShunt-EN.pdf

 

[Jmesduncan]

Man you’re awesome!! I have in my head I’d prefer to go with agm batteries but still not sure. If I wanted to go a step or two above the lead acid battery and was wanting the set up you explained with the dvsr and how it parallels and isolates the batteries basically as needed automaticly then what batteries would you recommend?? I finally got on the boat this morning to measure some stuff and get this picture you asked for. I’ve read some good and done negative reviews on this group 31 Duracell battery but I don’t remember the amp hours and kwh. If I wanted the next step or two above above lead acid and was ok with going around or even slightly over $250-$300 per battery so $500-$600 +/- some not including the wiring and dvsr and all, I know that’s extra, what would you suggest. The total wattage on the audio alone will be 2500 watts rms. Plus a small amount of leds. My usual usage would be a couple hours on the sandbar every weekend. Maybe 4-5 hours and say at night I’d like to leave the LEDs on while at the marina for say 2-4 hours. I love the system you described with the management system how it charges the batteries with the alternator one at a time and automatically swaps when one is charged.

 

[Jmesduncan]

Also I had the idea of getting a good strong start battery and then buying a stronger house battery to run the sound system and all. What do you think about this?? This is the agm battery I’ve found that I’m thinking would be a good one. This kinetic 2400 paired with a good deep cycle start battery or some other start battery that would go well with it. Or could I go two of these or what? Also would this agm battery charge gone off my alternator while riding until I get back to the dock to plug up?? I think you see where I’m trying to go. I’d rather have a little overkill for performance and peace of mind than try to save as much money as possible. I don’t have endless finances but some thing are worth doing right.

 

[FSH 210 Sport]

thanks for the pic!

Long story short, after all the research I did on LiFePO4 batteries, go with Autozone Duralast deep cycle marine batteries, or perhaps the Interstate low end deep cycle marine batteries for best bang for the kWh batteries. As I said above the AGM batteries are sealed which means no possibility of acid. I think both Autozone and Interstate make AGM batteries in group 31 size.


The hybrid system of a lead acid start battery and the LiFePO4 house battery is what I have, and would totally work, but you would need to install a DC to DC charger to protect your alternator. I’d have to research that a bit more to be sure on the specifics. The short version is you would have plenty of house battery capacity for what you want to do with a group 31 100Ah LiFePO4 battery. I have a group 24 AGM start battery and a Battle Born 100 Ah (1232 watt hour) lLiFePO house battery. That BB battery is about $900… but it will last you well over 10 years.

I suggest you click on the link in my signature line about the battery upgrade. There’s a lot of great info in there about my journey of upgrading and a lot of great input from other members.

https://jetboaters.net/threads/conversion-to-lifepo-batteries.35834/

My suggestion to you is to go full boat if you can afford it. With that set up you will never have to worry about how much battery you have left, but it’s not going to be cheap. Had I known then what I know now that is the system I would have gone with. But I get it if that is not in the budget. Either way we can set you up with a good system.

 

[Jmesduncan]

https://www.amazon.com/Enjoybot-100Ah-2000-5000-Lifetime-Off-grid/dp/B09CPWMZBZ/ref=mp_s_a_1_31?crid=2MKVGJH42BIMF&keywords=125+ah+lithium+battery&qid=1670686957&sprefix=lithium+battery+125+%2Caps%2C100&sr=8-31&ufe=app_do%3Aamzn1.fos.c3015c4a-46bb-44b9-81a4-dc28e6d374b3

what do you think about this or something like it??

 

[FSH 210 Sport]

There are only two battery companies that I found that had people to answer the phone and would answer my question, Relion and Battle Born. Of those two I suggest battle born, they have THE best BMS (battery management system) their customer service is great and all their csr’s are tech support people, they sell all of the components I have mentioned so far and know how to integrate them, and their batteries are made in the U.S.

The less expensive brands of LiFePO batteries are attractive due to their price but there is either no support or weak support at best. IMHO I would only buy BB batteries.

 

[Jmesduncan]

Advance Auto Parts - Down for Maintenance

Two of these with the dvsr setup you mentioned earlier is what I’m thinking right now with what all you’ve said.

Amazon.com

this seems to be the same switch/dvsr in your post. So with two of the above batteries and this switch I’d have the set up you mentioned basically ??

 

[FSH 210 Sport]

Advance Auto Parts - Down for Maintenance

Two of these with the dvsr setup you mentioned earlier is what I’m thinking right now with what all you’ve said.

Amazon.com

this seems to be the same switch/dvsr in your post. So with two of the above batteries and this switch I’d have the set up you mentioned basically ??

For some reason that doesn’t look right..I put that part number in on the BEP web site and there isn’t one, I suspect that is some sort of knock off….

From the BEP website:

Square Battery Distribution Cluster for Single Engine with Two Battery Banks

The 716-SQ-140A-DVSR is an ideal replacement for a battery selector switch. Just remove the selector switch and connect the existing wires to a 716 cluster, no extra wires are required for a fully automatic battery management system. To be used in single outboard dual battery bank or single...

www.bepmarine.com

This is the correct one on Amazon:

https://www.amazon.com/BEP-Square-Battery-Distribution-Cluster/dp/B0184S2S5Y/ref=sr_1_5?keywords=BEP&qid=1670767537&sr=8-5