Battery set-up

[Tizzler110]

Hi all-I’m relatively new to boat electrical set-up. I attached a photo of my current battery set-up installed by a local shop. There are two deep cell batteries connected to a switch. I typically use Battery number to setting as that is the one connected to the main motor. My question is when running the trolling motor which is attached to battery number one on the right i’d like to confirm that the only battery providing voltage is battery number one. I know this seems like an easy question, I am relatively new to boat ownership, and just trying to fully understand the set up I have and how to use it correctly. My ultimate goal is to make sure that when I’m running the trolling motor that it is not pulling any voltage from my starting battery.

 

[mike_i]

You said "I typically use Battery number to setting as that is the one connected to the main motor." I have no idea what you mean and the picture doesn't help much. Why don't you simply disconnect the starting battery and see if the trolling motor runs.

 

[Tizzler110]

Thanks, the batteries are on a PERKO switch. In the picture, the battery on the left is battery #2 on the switch and the one on the right is battery #1 on the switch. The shop hooked the trolling motor up to battery #1 on the right. This is why when I run the boat I set the switch to #2 so I’m not using the same battery to start the engine as run the trolling motor. Currently the trolling motor will run no matter what position the switch is in. I can try running the trolling motor and checking the voyage on each battery to confirm That it can only pull power from battery #1. Thanks again for all the help!

 

[mike_i]

Is the trolling motor connected directly to the battery, hopefully fused, or to the switch? Sounds like it's direct to the battery. If that's true the TM will run no matter what position the switch is in. Sounds like the existing switch only selects which battery will be the starting battery. You need another switch connected to the accessories like lights, radio and trolling motor to be able to switch the accessories between batteries.

 

[Tizzler110]

Thanks, Mike. Yes you are correct on the setup. The trolling motor is directly connected to battery #1 and runs no matter what the switch is on. As a note, the Bilge pump is also directly connected to battery #1. I looked at it again and the only thing the switch controls is the starting motor and auxiliary lights as when the switch is off none of the lights will work. I’ll looked into another switch great idea! In the meantime my only concern is when I run the trolling motor that it is only taking power from battery #1 as the two batteries are connected with a common ground.

 

[mike_i]

You could connect all of the accessories directly to battery number 1, thru the proper fuses, and leave just the motor on battery #2. Remember if you have the switch in the both or #2 position you'll be pulling current from the starting battery and run the risk of running it down. You should be good with your existing switch if you leave it in the #2 position. I have two switches on my boat but all that does is give me the option of being able to choose which battery I want to use for the starter and which to use for the accessories. After some deep thinking you'll be good with the one switch also the common ground is fine, it's the positive side of the battery that is being switched.

 

[eric102]

Interesting cable routing, right over the fill caps to make checking the acid levels more challenging.

 

[Tizzler110]

Thanks for all the help Mike!

 

[achris]

A few comments, mainly stemming from the photo...

1. Why are you using a deep cycle battery as a starting battery? Quickest way to kill a deep cycle battery is to use is as a a starting battery...
2. Who put the batteries into the holders like that? Not very clever. (I'm being very polite. ) Take one battery out and when you go to put it back in, HUGE risk of crossing the cables. The battery on the right (I assume it's #2 as it's nearer the ' 2 ' on the switch) should be swung 180 degrees. Both negs and both pos on the same side. Silly to do it any other way. You'll also have a shorter neg jumper cable.
3. Who's still using unsealed NON-MARINE batteries? That's OLD tech, like the 70's... Get those out of there and fit quality sealed MARINE batteries. Having non-marine batteries in a boat is asking for trouble.

Chris.......

 

[Faztbullet]

You NEVER tie your trolling motor to the main engine battery ..switch or no switch. The idea the motor will recharge battery's when running wont happen unless you have a 35amp system and its still not wired that way.

 

[dingbat]

A few comments, mainly stemming from the photo...

1. Why are you using a deep cycle battery as a starting battery? Quickest way to kill a deep cycle battery is to use is as a a starting battery...

Please explain the technical aspects of this comment.

Deep cycle batteries store more energy and are significantly more tolerate of deep discharge than a starting battery.

Properly sized, there is no downside to using deep cycle batteries in starting applications except the initial cost.

I’ve run twin DC batteries in every boat I’ve owned. My current Grp. 27 DC batteries are date coded 2010 and 2011.

3. Who's still using unsealed NON-MARINE batteries?

Meeee....waving my hands from the back of the room..lol

Probably 90% of the marine batteries sold today are lead acid technology.

Lots of "maintenance" free batteries but few, if any SLA (sealed lead acid) batteries large enough to use as a starting battery. You would have to jump up to Gel or AGM for a "sealed" battery.

I've run ​​​​​​​AC Delco RV lead acid batteries for years. Supposedly "maintenance free" but the caps are removable to replenish the electrolyte if the need arises. $130 per battery verse $325 for the same battery in AGM.

 

[mike_i]

I agree with dingbat. I have always used lead acid deep cycle batteries both for starting and running accessories.

 

[achris]

My god. How far behind the times are you guys? Haven't been able to buy an 'unsealed' lead acid battery here for about 2 decades!

Using DC batteries for starting.... :facepalm: The DC battery provides power for longer by its construction. The plates are thinner and more plentiful, giving a greater surface area to the electrolyte. But start pulling 200A and those plates get hot and start to buckle... THAT is why it's a bad idea to use DC batteries for starting... That's 'batteries 101'!

Chris....

 

[mike_i]

Where do you live where you can not buy an unsealed lead acid battery? I'm really confused. Are we referring to the same thing? I have two batteries on my boat. I have one battery in each of my vehicles. They are lead acid, they have a cap on each cell allowing me to remove said cap and visually see the level of sulfuric acid/water. If I wanted to I'd be able to insert a hydrometer into said cell to check the specific gravity of each cell.

 

[dingbat]

The DC battery provides power for longer by its construction. The plates are thinner and more plentiful, giving a greater surface area to the electrolyte. But start pulling 200A and those plates get hot and start to buckle...

I would be interested to see any technical docs you have to back up this claim.

East Penn Manufacturing (largest US battery manufacturer) has a little different philosophy

http://www.dekabatteries.com/assets/base/0149.pdf

For light to mode rate-duty low amp draw service, choose the dual purpose battery, specially designed to handle both starting and cycling.

For heavy-duty cycling, choose the deep cycle battery. This will give you enough cranking amperage to start your engine, and the most reserve power to keep your trolling motor and accessories running longer.

http://www.trojanbattery.com/Tech-Support/FAQ/BatterySelection.aspx?old=aspx

Can I use my deep-cycle battery as a starting battery?
deep-cycle batteries can be used for engine starting but starting batteries should not be used for deep-cycle applications. A deep-cycle battery may have less cranking amps per pound than a starting battery, but in most cases a deep-cycle battery is still more than adequate for the purpose of starting an engine

 

[achris]

Where do you live where you can not buy an unsealed lead acid battery? I'm really confused. Are we referring to the same thing? I have two batteries on my boat. I have one battery in each of my vehicles. They are lead acid, they have a cap on each cell allowing me to remove said cap and visually see the level of sulfuric acid/water. If I wanted to I'd be able to insert a hydrometer into said cell to check the specific gravity of each cell.

Yes, that's exactly the battery I'm referring to. ALL lead-acid batteries sold here, for at least the last 20 years have been fully sealed. No caps.... You're living in the 80's my friend.... In 2003, Toyota were putting old 'non-sealed' batteries in their Camrys. People were pointing and laughing....

 

[mike_i]

If I'm living in the 80's you're living in denial. Here are a few pictures of one of my many deep cycle batteries that I'm using in one of my solar power systems at home. It's the easiest battery to get to but believe me I have many more and they are no older than 3 years old. I'm not trying to get into a pissing match with you but is this the non sealed lead acid battery that you claim don't exist.

Yes, that's exactly the battery I'm referring to. ALL lead-acid batteries sold here, for at least the last 20 years have been fully sealed. No caps.... You're living in the 80's my friend.... In 2003, Toyota were putting old 'non-sealed' batteries in their Camrys. People were pointing and laughing....

 

[achris]

I'm not in denial. You are living in the dark ages.Modern batteries haven't had cell caps for over 20 years. I have no idea where you're buying your batteries. Maybe old stock.

I have 2 batteries in my boat, and most of my friends and relatives also have 2 batteries in their boats. My car has also 2 of the same batteries. My wife's car and my mother's car, and those of other relatives and friends. I maintain most of them. The only capped battery I have seen was in that 2003 Toyota, and Toyota got roasted for using old tech!

Here is a photo of the starboard battery in my car. Not a cap to be seen.

Chris......

 

[achris]

Here's a few more...

My car (Toyota Landcruiser 100), port side (main battery)


My boat, starboard side (battery #1)


My boat, port side (battery #2)


I also have a couple of others, the wife's car, and another friend. Access in a few hours.

As I said, can't buy old tech batteries here anymore... (and with good reason)

Here's a few websites of local parts shops, the batteries available. See if you can find a capped battery...

https://www.supercheapauto.com.au/sh.../car-batteries
https://www.repco.com.au/en/globes-b...s/c/1862917987
https://www.autobarn.com.au/batteries-globes-electrical/batteries

And this company sells nothing but batteries...
http://www.goodchild.com.au/automoti...enger-starting

Chris......

 

[mike_i]

That's fine that you have many sealed lead acid batteries. And I'm fine with my non sealed lead acid batteries. Here are a few links to non sealed lead acid batteries that are currently for sale. Notice the removable tops.

http://www.batteriesinaflash.com/int...iABEgIgtfD_BwE

https://www.autozone.com/exterior-ac...E&gclsrc=aw.ds

https://www.batteriesplus.com/produc...SABEgJ94vD_BwE

• Chemistry: Lead Acid
• Cranking Amps: 800
• Lead Acid Design: Flooded
• Maintenance Free: No

Your comment " I have no idea where you're buying your batteries. Maybe old stock."

is so ignorant I won't respond. Like I said I'm not here for a pissing match or to change your mind. Maybe the state you live in does not allow non sealed lead acid batteries, in California it's one of our few remaining freedoms we have. Enjoy your batteries and I'll enjoy mine, with all due respect it's time to move on.