Adding 3rd Battery

[MLA]

The switches offered by Malibu are make before break, so it is safe to switch between any of the ON positions. Just do not switch to or through OFF with engine running. 

[CopperDave]

Used the search bar to dig up this thread. I am planning on adding a third battery just as Dirtysidedown did this winter.  I am going to combine the 2 group 24’s the boat came with for the house bank and use a year old optima blue top group 24 AGM I have for the start battery. Will there be an issue with using or 2 wet cell batteries with an AGM battery it the switch was on “1+2”.  I have the “manual” four position type battery switch that has “off” “1” “2” “1+2” 

[shawndoggy]

1 hour ago, CopperDave said:

Used the search bar to dig up this thread. I am planning on adding a third battery just as Dirtysidedown did this winter.  I am going to combine the 2 group 24’s the boat came with for the house bank and use a year old optima blue top group 24 AGM I have for the start battery. Will there be an issue with using or 2 wet cell batteries with an AGM battery it the switch was on “1+2”.  I have the “manual” four position type battery switch that has “off” “1” “2” “1+2” 

optima says bad idea: https://www.optimabatteries.com/experience/blog/can-i-connect-dissimilar-batteries-in-parallel/

[gregtay]

I have been thinking about adding a dedicated(3rd) stern turn battery. Isolate stern turn from the rest of the electrical system. Use a separate charger for the thruster battery and just let it ride.  If the ST battery gets low due to over usage on the lake... then oh well.  I do have the bigger alternator, so I could wire it up to charge the 3rd battery, but I am not even sure if that is needed, just charge manually at night.

[CopperDave]

5 hours ago, shawndoggy said:

optima says bad idea: https://www.optimabatteries.com/experience/blog/can-i-connect-dissimilar-batteries-in-parallel/

Thank you Shawndoggy. I didn’t even think to go the Optima website.  Well it looks like I need to buy a battery, I already have the cables I need just waiting for the dealer to fix a few gel coat issues.  

[Stevo]

9 hours ago, CopperDave said:

Thank you Shawndoggy. I didn’t even think to go the Optima website.  Well it looks like I need to buy a battery, I already have the cables I need just waiting for the dealer to fix a few gel coat issues.  

The site also warns about batteries not the same age, you may want 3 batteries.

I was considering adding a 3rd to my bank to help with the voltage draw of stern turn, but I have noticed when using Fed/rev in conjunction with ST the increased RPM (just above idle RPM) definitely counteracts the draw from ST, with the added bonus of being more effective moving the tank around

[Brandonloos21]

16 hours ago, shawndoggy said:

optima says bad idea: https://www.optimabatteries.com/experience/blog/can-i-connect-dissimilar-batteries-in-parallel/

Wait a second, I could have sworn that Malibu had used 2 different batteries stock on the battery switch, one cranking batt and one deep cycle batt for house, am I incorrect? Have they always been identical. 
 

I currently have house/stereo bank which is composed of flooded deep cycles, that are different from (what I believed to be) an Agm cranking battery. 
 

No bueno?

[cowwboy]

3 minutes ago, Brandonloos21 said:

Wait a second, I could have sworn that Malibu had used 2 different batteries stock on the battery switch, one cranking batt and one deep cycle batt for house, am I incorrect? Have they always been identical. 
 

I currently have house/stereo bank which is composed of flooded deep cycles, that are different from (what I believed to be) an Agm cranking battery. 
 

No bueno?

That is how mine is set up and have been running like that for years.

Golf cart batteries for stereo and a AGM back up for starting. But I also don't leave them in the 1+2 position which I think is where the problem comes in. 

[Stevo]

I guess there’s also the fact that they are in the battery selling biz 

Edited February 23, 2023 by Stevo

[CaptainMorgan]

1 hour ago, Brandonloos21 said:

Wait a second, I could have sworn that Malibu had used 2 different batteries stock on the battery switch, one cranking batt and one deep cycle batt for house, am I incorrect? Have they always been identical. 
 

I currently have house/stereo bank which is composed of flooded deep cycles, that are different from (what I believed to be) an Agm cranking battery. 
 

No bueno?

FWIW, chargers like the NOCO genius series have different settings for "12V" and "12V AGM"

i suspect combining diff age and capacity of flooded batteries is a 'small' deal, but my limited understanding is that AGMs are a different animal.

[shawndoggy]

2 hours ago, Brandonloos21 said:

Wait a second, I could have sworn that Malibu had used 2 different batteries stock on the battery switch, one cranking batt and one deep cycle batt for house, am I incorrect? Have they always been identical. 
 

I currently have house/stereo bank which is composed of flooded deep cycles, that are different from (what I believed to be) an Agm cranking battery. 
 

No bueno?

Both are at least SLA and of the same age tho right?  Combining batts of different ages and AGM + SLA = ?

Not an electrical engineer, but it's by understanding that whenever batteries of different ages / states of charge are combined that they will basically self-level to the lowest common denominator.  So old batteries will drag the new one down to their level.  Also consider that AGM full charge is 13v, whereas SLA is 12.6.  So the SLA will always be dragging down the full charge of the AGM.

2 hours ago, cowwboy said:

But I also don't leave them in the 1+2 position which I think is where the problem comes in. 

Methinks this is the answer.  My problem is my attention span is way too short to keep the switch flipped correctly.

[Brandonloos21]

36 minutes ago, shawndoggy said:

Both are at least SLA and of the same age tho right?  Combining batts of different ages and AGM + SLA = ?

Not an electrical engineer, but it's by understanding that whenever batteries of different ages / states of charge are combined that they will basically self-level to the lowest common denominator.  So old batteries will drag the new one down to their level.  Also consider that AGM full charge is 13v, whereas SLA is 12.6.  So the SLA will always be dragging down the full charge of the AGM.

Methinks this is the answer.  My problem is my attention span is way too short to keep the switch flipped correctly.

Okay, so this is correct, paralleling batteries of different type/size/age via hardwire in the SAME BANK is no good. Will drag down to lowest voltage and AH capacity. But having them on perk switch is okay, as long as all battieries that are HARDWIRED connected in a bank must be same. Having 2 diff banks of different types of batts on different perk settings (1 vs 2) is okay, if you are using correct onboard charger and correctly using the perk (meaning only ever operating on one bank). 
 

I’ll be using pronautic 1250p which can charge multiple banks of diff battery types. When under way I’ll only operate on one bank depending on how depleted the large house/stereo bank is (alt strain). 

Edited February 23, 2023 by Brandonloos21

[CopperDave]

My plan was to use the two battery's it came with “same size, type and age” and Parallel the on position “2” for house/stereo bank. The third on position “1” for a start battery. I was unsure if mixing the SLA and AGM. I also use NOCO charger and noticed the different settings for the two different types of battery’s.  I am going to skip using the AGM and buy 1 SLA for the start battery. I don’t think running it in the “1+2” position will harm it with all the battery’s being the same type and size. 

[Brandonloos21]

14 minutes ago, CopperDave said:

My plan was to use the two battery's it came with “same size, type and age” and Parallel the on position “2” for house/stereo bank. The third on position “1” for a start battery. I was unsure if mixing the SLA and AGM. I also use NOCO charger and noticed the different settings for the two different types of battery’s.  I am going to skip using the AGM and buy 1 SLA for the start battery. I don’t think running it in the “1+2” position will harm it with all the battery’s being the same type and size. 

You would be OK with combining them, as long as you responsibly use the perko switch, and wire/program your NOCO accordingly. 

[CopperDave]

I am going to be getting another charger as well. I don’t think I will be running much if at all in the “1+2” position. Jut wanted more AH for running the stereo. I really drains the battery’s since I swapped out the DSP amps.  

[Brandonloos21]

6 minutes ago, CopperDave said:

I am going to be getting another charger as well. I don’t think I will be running much if at all in the “1+2” position. Jut wanted more AH for running the stereo. I really drains the battery’s since I swapped out the DSP amps.  

What model do you currently have? What model are you looking to upgrade to?

[CopperDave]

I have 2 genius 5.  Was thinking to just get one more but now I’m thinking about just going with the gen5X3.  

Edited February 23, 2023 by CopperDave

[Brandonloos21]

21 minutes ago, CopperDave said:

I have 2 genius 5.  Was thinking to just get one but now I’m thinking about just going with the gen5X3.  

You can either do that or the 10x2 / 10x3 

[CopperDave]

3 minutes ago, Brandonloos21 said:

You can either do that or the 10x2 / 10x3 

I was looking at the 10amp chargers as well. I just don’t know what to do with the 5’s I have.  

[Brandonloos21]

10 minutes ago, CopperDave said:

I was looking at the 10amp chargers as well. I just don’t know what to do with the 5’s I have.  

Sell em!

[timmypop]

I have a 2020 25 LSV. I have been having stern turn issues for some time. Two gold pully alternators replaced, wiring harness replaced, batteries replaced. I would keep getting low pump warning which had us chasing our tails thinking it was engine related. Malibu is now stating it could be ST. 

They are offering to replace my (1, 2, 1+2) switch with a VSR as well as change both batteries to AGM. I'm not convinced that will do it. I usually run in 1+2. Seems I need more bank power. I use the ST sparingly.  

1. What are your opinions on the suggestion to upgrade to VSR and dual AGMs? 
2. Maybe I should just add another AGM for good measure. I don't want to have to start on 1, then switch to 2 as stated above. 
3. I have two brand new 6v golf cart batteries sitting in the garage for another project, could I introduce that into the system for benefit? 

I have a Noco Gen2 2 Bank 20A

[Surf4FamFun]

39 minutes ago, timmypop said:

I have a 2020 25 LSV. I have been having stern turn issues for some time. Two gold pully alternators replaced, wiring harness replaced, batteries replaced. I would keep getting low pump warning which had us chasing our tails thinking it was engine related. Malibu is now stating it could be ST. 

They are offering to replace my (1, 2, 1+2) switch with a VSR as well as change both batteries to AGM. I'm not convinced that will do it. I usually run in 1+2. Seems I need more bank power. I use the ST sparingly.  

1. What are your opinions on the suggestion to upgrade to VSR and dual AGMs? 
2. Maybe I should just add another AGM for good measure. I don't want to have to start on 1, then switch to 2 as stated above. 
3. I have two brand new 6v golf cart batteries sitting in the garage for another project, could I introduce that into the system for benefit? 

I have a Noco Gen2 2 Bank 20A

I don't see the downside of getting an ACR switch and upgrade to AGM batteries on the Malibu dime.  You say VSR, I am presuming you mean the Blue Sea VsR that they call an ACR.  With that setup you turn the batteries on and off, there is a combined position but it is not normally used so there is no start on 1 and switch to 2 involved.  No clue from your problem description if the upgrade stands a chance of fixing things but it is an upgrade and it is free.  Unless letting them install and trying that solution will ruin a weekend if it does not fix it then let them give that a shot would be my suggestion.  If you are a first owner on a 2020 you should be under warranty, if you start making mods that do not follow factory specifications/build depending on the dealer they might not want to continue warranty work.

We have a ST in our 2021 23 MXZ (which weighs dry about what your 25 does) and as long as you bump the ST switch (preferably with the boat in gear and above idle) and don't have issues, we did get the 170 amp alternator.  Even days with several new riders turning around constantly we do fine.  The key to ST and battery voltage is to bump the switch, the boat will turn just about as fast running the ST 1/4 of the time you are turning as it will running continually.  Not sure if by "sparingly" you mean not often or in bursts as I described.  The first time we took the boat out I was not bumping the ST and we got low battery warnings later in the day.

[Stevo]

I am using 2 AGM group 31’s in my 22-25lsv and haven’t had any issues . I was think about adding a 3rd battery to the bank to aid in the voltage drop from using stern turn but haven’t pulled the trigger yet.

I do like the AGMs better because of their ability to sit on their side which has allowed to fit them in the compartment under the bow cushion 

Edited March 30, 2023 by Stevo

[Slayer]

55 minutes ago, Stevo said:

I am using 2 AGM group 31’s in my 22-25lsv and haven’t had any issues . I was think about adding a 3rd battery to the bank to aid in the voltage drop from using stern turn but haven’t pulled the trigger yet.

I do like the AGMs better because of their ability to sit on their side which has allowed to fit them in the compartment under the bow cushion 

I need to do this.