How many Batteries do you run?

[madmatt]

I have an '08 MB B52V23. Want to know what type of battery set ups are out there. My boat came with two marine starting batteries, but with two or three amps powering my stereo these batteries will die quick in the cove, right? I am looking at replacing them with 2 AGM batteries and an "add a battery" switch which will automatically save one battery for starting if I kill one in the cove.
Any advise?

 

[FLWakeRider]

Re: How many Batteries do you run?

Currently, I only have a single battery setup, but I have no amplifier's running, just the head unit with speaks attached to it, but I have dealt alot with customizing audio instalations.

Is your all stereo wiring run through a distribution block? Should be two seperate blocks, one for Power and one for Ground. If not, then you can reroute all of your amps through a block at least on the power side.

Bascially, setup all of the stero equipment through one of the AGM battery and then run that to your alternator (Or through another distribution block). This may also require boosting the wire gauge coming out of the alternator on your engine (most likely not since the stereo already runs off of the alternator now).
That may sound kind of weird in text, but I can make a diagram of it.
I have never tried it. Never really heard of anyone worried about it while there motor was not running.

 

[lowkee]

Re: How many Batteries do you run?

I'd say at least get a deep cycle battery, as if you plan on running your amp'd stereo for more than an hour or so, you will likely deep cycle one of those starting batteries, which will cause them to fail prematurely.

Starter batteries have a thin honeycomb of lead (used for best surface area) in them, which decays on every charge. They are made ONLY for starting, which requires little recharging to recover from. Deep cycles, on the other hand, have a lead block in them, which takes much longer to decay and is also why they don't make for good starting batteries (although if it turns your engine over, it can be used as a starting battery..).

Others will lead you to the best path for charging and connecting those batteries, but I can say those starting batteries will be permanently dead in no time if you use them for and amp'd stereo and lighting, etc.

 

[salty87]

Re: How many Batteries do you run?

i'm running 2 optimas, 2 amps = 1300 watts...nothing huge

you'll want a starting and a deep cycle as you've already read.

you can either use a manual switch to keep the loads separate, an isolator or a relay. i use a stinger relay (sr 200). there are no switches to remember and isolators can get expensive. the stereo is limited to the stereo batt(s) and there's a dedicated battery for starting the engine and it's all charged by your alternator.

every system is different though. if you want more play time for the cove and won't be running the engine to charge up, there's really no substitute for more batteries.

some people use golf cart batteries (6v)...cheaper, heavier, and last longer than 12v batteries.

 

[ZK]

Re: How many Batteries do you run?

I've used battery isolators before. In boats and trucks. Currently my plow truck has a battery isolator. I think it ran me $30.

Isolators let you have a deep cycle and a starter in one vehicle, and it charges both batteries while the engine is running, and will let you fully deplete the deep cycle, while still giving you the starter to start and run off of.

I prefer this, like stated above, because there are no switches, and it's idiot proof.

 

[madmatt]

Re: How many Batteries do you run?

Awesome help. I am going to try one starting batt and one deep cycle for this season (or until I determine I want another batt for the music). Definetely will look at an isolator to. First day of spring tomorrow, time to hit the cold water!

 

[Opossum]

Re: How many Batteries do you run?

I have been doing audio and video for over 10 years and let me tell you a isolator is not your best choice. An isolator uses 2 diodes in a Y config. The single input is what comes from the alt then the V part each has a diode. The reason these are not great options is voltage drop which eats your charging power and wastes it in heat. I have also seen them catch fire from trying to pass to much current passing through the diode trying to charge a very low battery. Your best options are a manual switch or a high amp relay (not a starter relay) like the Stinger mentioned above. I have redone a number of boat audio systems that were not wired correctly. It seems alot of companies and installers are using to small of power wire for these high power systems they are installing. Which causes even more issues.

Thats my $.02 worth spend as you see fit.


On a side note I have found most outboards have a joke of an alt ranging from 1-15amps. Not enough to recharge a drained battery or 2. I would install a system to recharge you batteries using shore power. Either and on board charger or like I will do on my boat a bank of batteries just for the audio system not connected to anything else in the boat and will be recharged when in the slip or on the shore.