Sponsored

DIY Dual Battery Setup

jmdwifi

Well-Known Member
First Name
John
Joined
Dec 23, 2019
Threads
22
Messages
654
Reaction score
785
Location
Virginia
Vehicle(s)
2025 Rubicon X
Occupation
Wireless Network engineer, Drummer of WOLF LEGION
How much was this? I’m curious because i installed the genesis system in my 2020 and it worked great but it is expensive.
Sponsored

 
OP
OP
Mr._Bill

Mr._Bill

Well-Known Member
First Name
Bill
Joined
Jul 22, 2019
Threads
38
Messages
6,645
Reaction score
7,721
Location
North Las Vegas, NV
Vehicle(s)
2023 Gladiator High Altitude - 2013 Nissan Leaf SV
Vehicle Showcase
1
How much was this? I’m curious because i installed the genesis system in my 2020 and it worked great but it is expensive.
I think it was around $500, but that was in 2019. I pulled all the pieces and moved it to my new truck in early 2024.
 

nasiraod

Active Member
Joined
Aug 21, 2025
Threads
5
Messages
37
Reaction score
30
Location
Vancouver, Canada
Vehicle(s)
2025 Golf R, 2020 Jeep Gladiator Rubicon
Occupation
Hardware Engineer
Sorry to resurrect an old thread, but I'm curious
Have you had any issues with charging the third battery? Since JTs use a computer controlled alternator that changes the voltage output below 13.7 consistently, most smart isolator cut off below that voltage. I'm thinking of using a simple ignition controlled solonoid, anyone think there are any issues with that?

Jeep Gladiator DIY Dual Battery Setup 17802005718902798856932905207210
 

ShadowsPapa

Well-Known Member
First Name
Bill
Joined
Oct 12, 2019
Threads
247
Messages
40,440
Reaction score
53,854
Location
Runnells, Iowa
Vehicle(s)
'25 JTMX, '23 JLU 4xe, '82 SX4, '73 Javelin
Occupation
Retired auto mechanic, frmr gov't ntwrk security admin
Vehicle Showcase
3
Sorry to resurrect an old thread, but I'm curious
Have you had any issues with charging the third battery? Since JTs use a computer controlled alternator that changes the voltage output below 13.7 consistently, most smart isolator cut off below that voltage. I'm thinking of using a simple ignition controlled solonoid, anyone think there are any issues with that?

17802005718902798856932905207210.webp
Mine charges in the 14s most of the time unless I have driven it a lot or for a while, then drops to 13.4 unless I put the charger on it (don't drive often these days - no reason to)

Anyway - unless that battery is an AGM - DO NOT DO THAT.
The IBS is also figuring on the two batteries of the size it's expecting. Toss in more capacity and you may have other issues down the road.
But never ever directly connect anything other than like type batteries together. (and a solenoid would be a direct connection when running)

If your third battery is not AGM - forget it.
 

nasiraod

Active Member
Joined
Aug 21, 2025
Threads
5
Messages
37
Reaction score
30
Location
Vancouver, Canada
Vehicle(s)
2025 Golf R, 2020 Jeep Gladiator Rubicon
Occupation
Hardware Engineer
Mine charges in the 14s most of the time unless I have driven it a lot or for a while, then drops to 13.4 unless I put the charger on it (don't drive often these days - no reason to)

Anyway - unless that battery is an AGM - DO NOT DO THAT.
The IBS is also figuring on the two batteries of the size it's expecting. Toss in more capacity and you may have other issues down the road.
But never ever directly connect anything other than like type batteries together. (and a solenoid would be a direct connection when running)

If your third battery is not AGM - forget it.
That is such a great point, I forgot to mention that I chose an AGM battery precisely for that reason, in the future, if I want to go to lithium then I'll switch to DC-DC charger
But for now, given that I have an AGM battery as a third, do you think there are any issues with a solonoid tied to ignition?
Main concern I have is if the third battery is depleted, and I try to start the vehicle, it would put extra strain on the starting battery. But it should be fine, I think

Or do you think the following is better?
https://a.co/d/0h3vP1Gq
This has a cut in of 13.3 and cut off of 12.8, looks promising, and I don't have to have an ignition wired
 

Sponsored

OP
OP
Mr._Bill

Mr._Bill

Well-Known Member
First Name
Bill
Joined
Jul 22, 2019
Threads
38
Messages
6,645
Reaction score
7,721
Location
North Las Vegas, NV
Vehicle(s)
2023 Gladiator High Altitude - 2013 Nissan Leaf SV
Vehicle Showcase
1
Sorry to resurrect an old thread, but I'm curious
Have you had any issues with charging the third battery? Since JTs use a computer controlled alternator that changes the voltage output below 13.7 consistently, most smart isolator cut off below that voltage. I'm thinking of using a simple ignition controlled solonoid, anyone think there are any issues with that?

17802005718902798856932905207210.webp
I have not had any issues with the Smart Isolator used. It connects the third battery after the engine is started. It disconnects after shutdown when the voltage level difference exceeds a certain point. The system doesn't have any trouble charging all the batteries. The third battery is a AGM marine battery.
 

nasiraod

Active Member
Joined
Aug 21, 2025
Threads
5
Messages
37
Reaction score
30
Location
Vancouver, Canada
Vehicle(s)
2025 Golf R, 2020 Jeep Gladiator Rubicon
Occupation
Hardware Engineer
I have not had any issues with the Smart Isolator used. It connects the third battery after the engine is started. It disconnects after shutdown when the voltage level difference exceeds a certain point. The system doesn't have any trouble charging all the batteries. The third battery is a AGM marine battery.
Fantastic, I just ordered the smart isolator from Amazon, thank you very much

Just curious, do you remember where you got the battery box you installed underneath the truck? Might want to go that route in the future
 
OP
OP
Mr._Bill

Mr._Bill

Well-Known Member
First Name
Bill
Joined
Jul 22, 2019
Threads
38
Messages
6,645
Reaction score
7,721
Location
North Las Vegas, NV
Vehicle(s)
2023 Gladiator High Altitude - 2013 Nissan Leaf SV
Vehicle Showcase
1
Fantastic, I just ordered the smart isolator from Amazon, thank you very much

Just curious, do you remember where you got the battery box you installed underneath the truck? Might want to go that route in the future
This is the one I purchased. Back in 2019, the Stainless Steel version was $99.

https://a.co/d/05bcxCFS
 

nasiraod

Active Member
Joined
Aug 21, 2025
Threads
5
Messages
37
Reaction score
30
Location
Vancouver, Canada
Vehicle(s)
2025 Golf R, 2020 Jeep Gladiator Rubicon
Occupation
Hardware Engineer
OP
OP
Mr._Bill

Mr._Bill

Well-Known Member
First Name
Bill
Joined
Jul 22, 2019
Threads
38
Messages
6,645
Reaction score
7,721
Location
North Las Vegas, NV
Vehicle(s)
2023 Gladiator High Altitude - 2013 Nissan Leaf SV
Vehicle Showcase
1
Thank you very much, I really appreciate it 👍
Another question, where did you ground your battery in the back there?
I ran the Warn cable to the front and made the battery connection and ground there.
 

nasiraod

Active Member
Joined
Aug 21, 2025
Threads
5
Messages
37
Reaction score
30
Location
Vancouver, Canada
Vehicle(s)
2025 Golf R, 2020 Jeep Gladiator Rubicon
Occupation
Hardware Engineer
I ran the Warn cable to the front and made the battery connection and ground there.
Thank you very much, I really appreciate it
That was my initial plan, was hoping for a shortcut, but, I think I'll stick to it then 👍
Sponsored

 
 







Top