Dual batteries

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Another option is National Luna. Ive had their dual battery kit on my 60 for about 3 years now with the 2f and the 5.3. Its been pretty good so far. I still keep a Noco jump box in my truck, and the second battery basically just runs my fridge and baby monitor camera... or i run them in parallel when i use my winch.

The national luna has a solenoid that isolates your starting battery at key off and at start up, and after 5 min or if your starting battery reaches full charge of 14v or whatever you can hear it clunk and it will run the two batteries in parallel to charge the second battery off of the alternator. It also has this ugly clunky battery voltage indicator for the inside of the truck that i kind of hate but its nice to have.

I mounted and did all of my stuff exactly like how @Godwin did his
I like the idea of the National Luna setup, but I agree that their voltage indicator needs to be redesigned or have other options 😂
 
I like the idea of the National Luna setup, but I agree that their voltage indicator needs to be redesigned or have other options 😂
haha they have a digital screen for their DC Converter, but it doesnt work with their dual battery kit unfortunately. I was thinking abotu adapting it to the iron man dual battery monitor screen, but youd lose the ability to switch the batteries into parallel
 
Another option is National Luna. Ive had their dual battery kit on my 60 for about 3 years now with the 2f and the 5.3. Its been pretty good so far. I still keep a Noco jump box in my truck, and the second battery basically just runs my fridge and baby monitor camera... or i run them in parallel when i use my winch.

The national luna has a solenoid that isolates your starting battery at key off and at start up, and after 5 min or if your starting battery reaches full charge of 14v or whatever you can hear it clunk and it will run the two batteries in parallel to charge the second battery off of the alternator. It also has this ugly clunky battery voltage indicator for the inside of the truck that i kind of hate but its nice to have.

I mounted and did all of my stuff exactly like how @Godwin did his

thanks for the feedback... I'm aware of the national luna and i've been reading about that. I'm not clear off hand ...but it seems that the blue-sea smart relay does about the same thing or close...but of course you have to provide the related wiring etc I have a dual battery setup now but its the old school deal with two batteries connected by a heavy duty cable to joins the two batteries at the pos terminal.

In your configuration are you running two "crank" batteries or one crank battery and one deep cycle or other type battery? My battery setup is fairly similar...I have the stainless trays and batteries set there... of course my wiring is different as I'm in the "simple setup" . I'll read through this thread again and I'm going to look at what I might see. These REDARC or other brand dc to dc chargers look interesting, but not sure how much money I want to throw at this. Space is also limiting and I have a fuse box related to the 5.7 vortec under the hood too.
 
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I'd have to check the size. One battery is an Interstate and the other a Walmart brand. Yes, this system continues to work. I generally have the secondary battery offline, or disconnected, and only switch to both to top off the charge. When winching I'll generally connect both. I manually connect or disconnect the batteries, there is a way to activate the switch when the ignition is on and disconnected when off but I have not tried to set that up. I learned that if batteries are left connected over a day or two they will drain. I think it may be due to keeping the magnetic switch on. I've used this setup once or twice for a self jump start which came in very handy.

I've been running two 34 case size start batteries (twins), I think the 27 case size fits too. I recently had a secondary battery failure and now is the time to look at options and setups before I buy batteries again. Was wondering if you were just running two old school traditional crank batteries or some other combination. Then I find out NAPA stopped making or selling the 800CCA batteries I like, so I've been looking around. I need to do some wiring clean up any way and this is part of that as well. Off hand I 'm trying to decide if I do the blue sea smart relay and if so what combination of battery types. Likely I'm going to setup a cutoff switch on teh secondary battery between the loads and the battery so when I choose I can simply turn off the loads (vehicle parked), my truck is not my daily driver so it sits a lot.

I don't claim its the "smart" setup...but I have two crank batteries connected by 2 gauge cable on the pos terminals. Trying to understand if I'm doing something that contributes to the secondary battery dying early. Again this truck does a lot of sitting etc so I know I'm not putting it under crazy amp loads...but I know long term storage is not good on batteries, Anyway looking at options and want to have my mind made up before I go buy two more batteries at approx $200 or more each.

before recent battery faiilure I'm seeing 14.XX voltage at the primary battery and around 14.XX (very minor difference) on the secondary battery. I follow that I'm not really seeing independent voltage numbers (given my 2 gauge cable that connects both batteries) but its the only info I have. I have a CS 144 alternator thats around 140 amps from memory (its a stock GM alternator) and my engine is a 5.7 vortec and I have good grounds with better cables on the grounds and the pos alt feed wire etc, and all related battery cables (vs the stock stuff)
 
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I've been running two 34 case size start batteries (twins), I think the 27 case size fits too. I recently had a secondary battery failure and now is the time to look at options and setups before I buy batteries again. Was wondering if you were just running two old school traditional crank batteries or some other combination. Then I find out NAPA stopped making or selling the 800CCA batteries I like, so I've been looking around. I need to do some wiring clean up any way and this is part of that as well. Off hand I 'm trying to decide if I do the blue sea smart relay and if so what combination of battery types. Likely I'm going to setup a cutoff switch on teh secondary battery between the loads and the battery so when I choose I can simply turn off the loads (vehicle parked), my truck is not my daily driver so it sits a lot.

I don't claim its the "smart" setup...but I have two crank batteries connected by 2 gauge cable on the pos terminals. Trying to understand if I'm doing something that contributes to the secondary battery dying early. Again this truck does a lot of sitting etc so I know I'm not putting it under crazy amp loads...but I know long term storage is not good on batteries, Anyway looking at options and want to have my mind made up before I go buy two more batteris at approx $200 or more each.

I can't help with answering the battery selection. I usually replace as needed with what's convenient. I started out with a pair of identical Interstate batteries from Costco, but when one died and I was traveling I went to the nearest Walmart for a replacement. Since these are seldom connected I don't think having mismatched batteries is an issue.

I'm still running a 2F and am planning on installing a second alternator in place of the smog pump to feed the secondary battery. Looking for redundancy - two batteries, two alternators, having a backup in case one dies.
 
I can't help with answering the battery selection. I usually replace as needed with what's convenient. I started out with a pair of identical Interstate batteries from Costco, but when one died and I was traveling I went to the nearest Walmart for a replacement. Since these are seldom connected I don't think having mismatched batteries is an issue.

I'm still running a 2F and am planning on installing a second alternator in place of the smog pump to feed the secondary battery. Looking for redundancy - two batteries, two alternators, having a backup in case one dies.

I don't know what style of secondary alternator you might try (Toy, GM , Aftermarket)...but at one time I had a one wire CS144 Alternator on my truck and it worked fine....(its only one wire that feeds the battery) I bought it that way (modified). Now I have a stock GM CS144 alternator I can basically buy anywhere if something happens... So far I've tried to stay that same choice logic with batteries...something that I can buy anywhere for the most part.
 
thanks for the feedback... I'm aware of the national luna and i've been reading about that. I'm not clear off hand ...but it seems that the blue-sea smart relay does about the same thing or close...but of course you have to provide the related wiring etc I have a dual battery setup now but its the old school deal with two batteries connected by a heavy duty cable to joins the two batteries at the pos terminal.

In your configuration are you running two "crank" batteries or one crank battery and one deep cycle or other type battery? My battery setup is fairly similar...I have the stainless trays and batteries set there... of course my wiring is different as I'm in the "simple setup" . I'll read through this thread again and I'm going to look at what I might see. These REDARC or other brand dc to dc chargers look interesting, but not sure how much money I want to throw at this. Space is also limiting and I have a fuse box related to the 5.7 vortec under the hood too.

I run two of the same batteries, but not because you have to, you can run different batteries with the National Luna system. The batteries i use are X2 Power deep cycle AGM batteries. They are kind of the best AGM battery you can get right now and made by northstar and designed by the original Odyssey people before it was sold off. They are pricey, but they have higher cold cranking amps than a Optima red top starting battery and have a higher capacity and reserve capacity than a yellow top. Since the specs on them are so good i just use two of them. You can get them at batteries plus and sometimes they run good discounts on them.

I honestly have never personally needed the dc dc capabilities in my truck. I feel like that is more geared to RVs and stuff who are using a TON of power. When i am camping the most i do is like charge my phone and run my fridge. I dont even use truck mounted area lights anymore because I use milwaukee lights for everything now. I am planning on swapping over to the higher output 140 amp GM alternator once my 105 amp 5.3 alternator dies but ive not had any charging issues or anything like that


you can kinda see the national luna solenoid behind my coolant reservoir bottle on the driver side.

F01D0vbh.jpg
 
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I run two of the same batteries, but not because you have to, you can run different batteries with the National Luna system. The batteries i use are X2 Power deep cycle AGM batteries. They are kind of the best AGM battery you can get right now and made by northstar and designed by the original Odyssey people before it was sold off. They are pricey, but they have higher cold cranking amps than a Optima red top starting battery and have a higher capacity and reserve capacity than a yellow top. Since the specs on them are so good i just use two of them. You can get them at batteries plus and sometimes they run good discounts on them.

I honestly have never personally needed the dc dc capabilities in my truck. I feel like that is more geared to RVs and stuff who are using a TON of power. When i am camping the most i do is like charge my phone and run my fridge. I dont even use truck mounted area lights anymore because I use milwaukee lights for everything now. I am planning on swapping over to the higher output 140 amp GM alternator once my 105 amp 5.3 alternator dies but ive not had any charging issues or anything like that


you can kinda see the national luna solenoid behind my coolant reservoir bottle on the driver side.

F01D0vbh.jpg

nice clean setup. I'm leaning towards likely going back to a single battery and cleaning up my wiring and see what happens from there. If I find I don't have enough "Power" then I'll re-visit the question....at least for my use. I think my crank battery is still good, I'm going to put it on charge outside of the truck for a few days and see what it does. It I have to buy something...I've not made up my mind on what to pick, in the past I've tried to stay with a battery from NAPA or autozone....should I need one on the road somewhere. Amazing...my battery problems so far have been here at home. I've read a lot about AGM...i'm not down on them and for everything I've read they are superior. I've also read good reviews on the National Luna setup . I do want a "sealed" battery...not one of these old school types with the caps, so far I'm leaning on trying to buy local.
 
nice clean setup. I'm leaning towards likely going back to a single battery and cleaning up my wiring and see what happens from there. If I find I don't have enough "Power" then I'll re-visit the question....at least for my use. I think my crank battery is still good, I'm going to put it on charge outside of the truck for a few days and see what it does. It I have to buy something...I've not made up my mind on what to pick, in the past I've tried to stay with a battery from NAPA or autozone....should I need one on the road somewhere. Amazing...my battery problems so far have been here at home. I've read a lot about AGM...i'm not down on them and for everything I've read they are superior. I've also read good reviews on the National Luna setup . I do want a "sealed" battery...not one of these old school types with the caps, so far I'm leaning on trying to buy local.
Thankfully your 5.7 has the charging amps to run an AGM. On the 2f i dont think the Alternator can keep up with charging an AGM. What are your use plans for the dual batteries? To be completely honest if i was to go back and do it again i wouldnt do the dual batteries at all. I would just only have one of these X2 power batteries and only use it as a starting battery.

For aux power for my fridge and phone charging and stuff i would just use a Jackery battery pack instead of the dual batteries and for jumping my truck if it dies my noco jump box. This would eliminate the second battery, all the wiring, and the solenoid and everything. I personally dont think I need 2 batteries but it looks cool in there i guess
 
Thankfully your 5.7 has the charging amps to run an AGM. On the 2f i dont think the Alternator can keep up with charging an AGM. What are your use plans for the dual batteries? To be completely honest if i was to go back and do it again i wouldnt do the dual batteries at all. I would just only have one of these X2 power batteries and only use it as a starting battery.

For aux power for my fridge and phone charging and stuff i would just use a Jackery battery pack instead of the dual batteries and for jumping my truck if it dies my noco jump box. This would eliminate the second battery, all the wiring, and the solenoid and everything. I personally dont think I need 2 batteries but it looks cool in there i guess
whats the capacity on your Jackery? I saw this dude on YT, seems to run a similar setup compared to duals

 
Thankfully your 5.7 has the charging amps to run an AGM. On the 2f i dont think the Alternator can keep up with charging an AGM. What are your use plans for the dual batteries? To be completely honest if i was to go back and do it again i wouldnt do the dual batteries at all. I would just only have one of these X2 power batteries and only use it as a starting battery.

For aux power for my fridge and phone charging and stuff i would just use a Jackery battery pack instead of the dual batteries and for jumping my truck if it dies my noco jump box. This would eliminate the second battery, all the wiring, and the solenoid and everything. I personally dont think I need 2 batteries but it looks cool in there i guess

I initially jumped into the dual battery game just on whim with no real plan, other than get the dual battery tray and get it basically functional. What I need to power is: two sets of off-road lights, radio (cb-ham/stero amp, electric powered front bmw seats, refrigerator (some times), ARB air compressor.

heavy amp load stuff would only run while engine running. Refrigerator when used, would generally run while engine is running and I would not have expectation that it would run too long with engine off. Stero amp is not crazy. I dont' know the amp load of the compressor but it would only run with engine running, then of course the 10K electric winch, winch would only run with engine running...unless I had some type of emergency.

I'm not a hard core camper, if I were to get to that point, I might consider one of the "smart REDARC" boxes and likley a battery back int the rear for sole use of the refrigerator. I'm not that person now, and it doubtful I will do that anyway

I might get one of the AGM batteries you noted, there is a battery plus store near me (@ decatur AL) I saw on the web...I might check that out , I was looking a pictures and the battery terminals seemed to be potentially different or they looked like that in pic. I of course would run the military type battery terminals I already have.

During this project stuff now , I'm going to install two HD bus bars (neg pos) where I can just run one rather large cable off the battery to feed the bus bar (pos and neg) back on the rear of the fender well, where my draw wires would then connect that way rather then the mess all going to the battery terminals...except for the winch will stay direct connected to the battery.

If anyone is looking for a very stable HD GM stock type alternator the CS144 is that. That was an optional ALT on 5.7 engines and others too, of course its not one of the smart ALT's that are around on certain newer model vehicles, it mounts on the 5.7 with no mods...and I think the basic alt on the 5.7 at that time was teh CS 130 if I have the model right. I'm a big fan of the CS-144.

and while I test this single battery setup, (once I go back which will happen soon), I'll be in the habbit of carrying around one of those noco battery jump boxes.
 
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I run two of the same batteries, but not because you have to, you can run different batteries with the National Luna system. The batteries i use are X2 Power deep cycle AGM batteries. They are kind of the best AGM battery you can get right now and made by northstar and designed by the original Odyssey people before it was sold off. They are pricey, but they have higher cold cranking amps than a Optima red top starting battery and have a higher capacity and reserve capacity than a yellow top. Since the specs on them are so good i just use two of them. You can get them at batteries plus and sometimes they run good discounts on them.

I honestly have never personally needed the dc dc capabilities in my truck. I feel like that is more geared to RVs and stuff who are using a TON of power. When i am camping the most i do is like charge my phone and run my fridge. I dont even use truck mounted area lights anymore because I use milwaukee lights for everything now. I am planning on swapping over to the higher output 140 amp GM alternator once my 105 amp 5.3 alternator dies but ive not had any charging issues or anything like that


you can kinda see the national luna solenoid behind my coolant reservoir bottle on the driver side.

F01D0vbh.jpg
did you get your x2 batteries at battery plus ? I've been debating on this or another option...but I would rather deal with a store that I'm close too rather than buying something like this over the internet and if there were problems you are pretty much "hosed". Another brand is only available over the internet based on what I see. At least with this brand I can deal with a store that's somewhat local. I was trying to find another option in interstate brand but the local people cannot get their story straight and are telling me one product number is the same as another...which of course is 100% wrong...noteablly when I can see the product list and specs on their own web site.

I was going to buy the x2 battery today at one specific store (south of me by 70+ miles) because they said they had it in stock when I called and I paid via the storefront on the web....and then I called back to see when I could come get it....and then I'm told (yeah we dont' have it in stock)...dumb and dumber. So I cancelled. If I'm going to have to go through the order process I might as well get it from a location closer to me. I guess when you call and ask if specific item #XXXXXX is in stock...that must mean something else to some people....
 
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I gave up on the fancy shmancy dual battery setup idea. Far too expensive with not enough upside.
In my experience of using both batteries really hard, they don’t last long.
So the best bang for the buck was two identical group 27 wet cell deep cycle batteries.
(I used to get mine at sears).

Easy to get, not too expensive. Performance was plenty good.

Yeah - I noticed faster starter turnover using an AGM battery, but so what. Engine would always start on wet cells too.
 
I run two of the same batteries, but not because you have to, you can run different batteries with the National Luna system. The batteries i use are X2 Power deep cycle AGM batteries. They are kind of the best AGM battery you can get right now and made by northstar and designed by the original Odyssey people before it was sold off. They are pricey, but they have higher cold cranking amps than a Optima red top starting battery and have a higher capacity and reserve capacity than a yellow top. Since the specs on them are so good i just use two of them. You can get them at batteries plus and sometimes they run good discounts on them.

I honestly have never personally needed the dc dc capabilities in my truck. I feel like that is more geared to RVs and stuff who are using a TON of power. When i am camping the most i do is like charge my phone and run my fridge. I dont even use truck mounted area lights anymore because I use milwaukee lights for everything now. I am planning on swapping over to the higher output 140 amp GM alternator once my 105 amp 5.3 alternator dies but ive not had any charging issues or anything like that


you can kinda see the national luna solenoid behind my coolant reservoir bottle on the driver side.

F01D0vbh.jpg
Showoff....
 
did you get your x2 batteries at battery plus ? I've been debating on this or another option...but I would rather deal with a store that I'm close too rather than buying something like this over the internet and if there were problems you are pretty much "hosed". Another brand is only available over the internet based on what I see. At least with this brand I can deal with a store that's somewhat local. I was trying to find another option in interstate brand but the local people cannot get their story straight and are telling me one product number is the same as another...which of course is 100% wrong...noteablly when I can see the product list and specs on their own web site.

I was going to buy the x2 battery today at one specific store (south of me by 70+ miles) because they said they had it in stock when I called and I paid via the storefront on the web....and then I called back to see when I could come get it....and then I'm told (yeah we dont' have it in stock)...dumb and dumber. So I cancelled. If I'm going to have to go through the order process I might as well get it from a location closer to me. I guess when you call and ask if specific item #XXXXXX is in stock...that must mean something else to some people....
I did order it from batteries plus. I did the order online and ship to the store and had them send it to a store that was like a mile from my house. They also took my old battery as a core at that store.
 
In hind sight, a jackery would eliminate that whole second battery and it would look even better in there haha
I'm curious about the Jackery thing now. Never even heard of those until this thread, so I'll have to do a little homework. I've planned to go dual batteries for many years but there's always been something pushing it down the list. Now with portable jumpstarters the starting redundancy is no longer necessary, and it sounds like the Jackery pretty much eliminates the need for a "house" battery. Seems the only thing necessary now that could justify a dual battery setup would be a winch.
 

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