Dual Batteries?

jcr159

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portage lakes, oh
First things first...

I'm operating on a series of small lakes that are 90% no wake... so mostly booze cruise type of use. Lots of anchoring/swimming, some tubing.

Since I'll be doing a good bit of anchoring and swimming with the radio and accessory use, should I think about a second battery? I'm used to boats on the Gulf in FL that almost always have 2 batteries and a switch to disconnect, etc. Is that total overkill? Am I paranoid? If not, any recommendations on equipment to install and set up a second battery?

thanks,
-j
 
I certainly do not think it's overkill to have 2 batteries. Especially if you're going to be anchored a lot using the radio, it's nice to have piece of mind to know that if one battery runs low that you always have a second battery to start the motor.
Lucky enough to have 2 batteries. If I didn't, my Titan GooLoo battery starter would be on board. And it's in the truck regardless.
 
Get the 2 batteries, if you find a boat with one your dealer can add a second .
 
I wouldn‘t even own a pontoon or tritoon WITHOUT dual batteries and perko switch. Overkill? Absolutely not. Just smart thinking and insurance. For the uses you mention, I’d see it as pretty essential myself.
 
We only had 1 battery on our Bennington for 12 yrs. Of course we always carried a jump pack if we ever needed it. My current boat has duel batteries, the perko switch and the Master switch on the dash. Love it!
 
Sounds like this is on the short list then…. Any advice on installing the switch aftermarket? What’s the best way to mount and get a factory look?
 
been boating for 32 years, I wouldn't have a boat without 2 batteries.
I've been boating for about the same time and have had 5 pontoons, a bow rider (and 5 PWC's). My current boat is the first with dual batteries. I'm glad I have them, but got along fine for 32 years without a second battery. I do usually have a lithium jump starter on board with me just in case.
 
I think I’ll probably carry the jump starter until I can get the second installed….

I gotta say though…. Costco has a sweet Duracell “generator “ (an inverter with a big Lipo battery) that was intriguing but expensive. That doesn’t help much though when someone forgets to shut off power, etc….
 
I have had pontoons for 34 years. Never had a problem that a single battery would have solved. My old cabin cruiser had dual batteries and dual bilge pumps and I had issues with complex switching. Extra complexity competes with redundancy.
 
I have dual batteries and carry a jump pack on board. I figure the jump pack would be likely used by others at tie-ups, etc before me, but always good to have. Can't be too safe.
 
if you have a couple of amps, subs , and like to float and listen to tunes 1 battery won't get it done. If you just cruise around and go back to the dock 1 will work. Depends on what you have pulling amperage and how you use your boat. JMHO
 
Hi everyone. Hoping to get this post reengaged. Would you install the batteries in parallel or just leave them as standalone? In parallel you can double your amp hours while maintaining the voltage.

thanks
 
Hi everyone. Hoping to get this post reengaged. Would you install the batteries in parallel or just leave them as standalone? In parallel you can double your amp hours while maintaining the voltage.

thanks

boat is at the dealer as i type for my 20 hour service... they are adding the second battery, and switch. there are a bunch of ways to do it, but most common is a switch that allows selecting battery 1, battery 2, both, or off... this affects supply to the boat electronics and cranking the motor. usually it's good practice to run in the "both" position when the motor is on, and switch to a single battery when on the hook or moored. This way, you'd always have a full battery to cut over to in case of emergency.

Which brings up the other side of things... charging... you may want a dedicated charge controller inline with the alternator to make sure the batteries are charged evenly. otherwise they can get out of sync and have some issues... it's complicated and i'll leave it at that for now... Dedicated charge controllers can sense which battery is low and direct charge there till they are within a spec, then send charge to both...
 
boat is at the dealer as i type for my 20 hour service... they are adding the second battery, and switch. there are a bunch of ways to do it, but most common is a switch that allows selecting battery 1, battery 2, both, or off... this affects supply to the boat electronics and cranking the motor. usually it's good practice to run in the "both" position when the motor is on, and switch to a single battery when on the hook or moored. This way, you'd always have a full battery to cut over to in case of emergency.

Which brings up the other side of things... charging... you may want a dedicated charge controller inline with the alternator to make sure the batteries are charged evenly. otherwise they can get out of sync and have some issues... it's complicated and i'll leave it at that for now... Dedicated charge controllers can sense which battery is low and direct charge there till they are within a spec, then send charge to both...
While it's at the dealer have them install an onboard battery charger too. During the season we use the boat enough to keep the batteries charged up. In the off season we just plug the charger in to keep both batteries charged and maintained without having to remove them from the boat.
 
Another opportunity for me to sell the Blue Sea SI-ACR for anyone with two batteries.

It's either on or off - no having to think about which battery to start with, which needs a charge etc. etc. Both your crank and house charge while running, unless crank voltage is below a set threshold and the relay charges the crank first, then combines. Also isolates when starting so your house devices don't lose voltage (sag) while you turn over your starter. Also isolates your crank battery from the house batt while hanging at the sandbar so you can get home.

Frankly this should be the standard for all 2 battery set ups.

I've linked this video before as this does an excellent job of describing the benefits and how it actually works.

 
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