DIY Dual Battery Setup

[Mr._Bill]

I'm putting in an Auxiliary Battery. Technically, this is a triple battery system, as the stock batteries will remain where they are. I'm going to post some pictures and update it as I work through the install.

I found a stainless steel battery box that fits behind the right rear wheel. I'll be using the Cole Hersee Smart Isolator that is in the Genesis Dual Battery System. I'll be adding a dual voltage display in the cab, and a button to activate the battery boost function. The wiring is probably more expensive than necessary, since I'll be using Warn pre-terminated cables with Quick Plugs to connect the battery in the back to the Isolator mounted by the battery. The battery will be a 34M deep-cycle Marine style.

I've now got the battery box mounted, and have ordered the smart Isolator and cables.

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[WhatExit?]

This is the first I’ve seen this. I’m interested to learn more about this- I hope the OP will follow up on his first post

 

[Mr._Bill]

This is the first I’ve seen this. I’m interested to learn more about this- I hope the OP will follow up on his first post

I have a lot of the work done. The cables are run, but need connected. I don't have a garage to work in, so everything is on hold while I wait for warmer weather.

 

[WhatExit?]

I have a lot of the work done. The cables are run, but need connected. I don't have a garage to work in, so everything is on hold while I wait for warmer weather.

can you provide more info on what and how you’re putting together?

 

[ShadowsPapa]

I'm wondering if this may be a way to power a trailer mounted winch on my car hauler, and for the receiver winch mount I am planning on for the future. Need to figure out how to power those things. Having a battery at or near the back is a good option.

 

[WhatExit?]

I'm wondering if this may be a way to power a trailer mounted winch on my car hauler, and for the receiver winch mount I am planning on for the future. Need to figure out how to power those things. Having a battery at or near the back is a good option.

You could do it by running HD cables from under the hood to a remote “house battery” - where you’d have a battery isolator so the 2nd battery doesn’t drain the Jeep’s main battery(ies).

there are many potential uses of a 2nd battery which is why I want to learn more about the OP’s setup and battery box installation.

 

[Mr._Bill]

My plan was to provide a separate battery to power the winch and lights, and possibly other items in the future. I didn't want issues with running the main battery too low, but wasn't willing to put out the $1200 for the Genesis kit and two new batteries. I also didn't really like the idea of removing the ESS battery from the system. I decided to try something a little more flexible, and hopefully less expensive.

The 'brains' of the setup is the Cole Hersee Smart Isolator. It allows front and rear batteries to be charged, use of both batteries for accessories, and prevents the main battery from being discharged too low to start the truck. Genesis uses a version of this in their dual battery kit. They even sell a model of their G Screen to work with this isolator.
Cole Hersee Smart Isolator
https://smile.amazon.com/gp/product/B00LMGPHW2/ref=ox_sc_saved_title_4?smid=A6AY1HFZHO49U&psc=1
Smart Isolator Wiring Diagram
https://m.littelfuse.com/~/media/co...lfuse-if-161-48525-smart-battery-isolator.pdf
Genesis G Screen
https://www.genesisoffroad.com/Genesis-Offroad-G-Screen-p/140-gs.htm

I used Warn cables with Quick Connect Plugs to power my winch, which is installed on a removable front receiver mount. They sell a cable kit (20 and 24 foot long) to put a Quick Plug at the rear of the vehicle. I'm using one of these to connect the battery in the rear box to the Smart Isolator and Winch in the front. The short version (usually attached to a winch) is connected to the rear battery, and the 7 foot version (used to provide a Quick Plug at the front) could also be used to connect to the rear battery and provide a Quick Plug at the hitch. I'm using the relay that comes in the long cable kit with an AUX button to control power to the Quick Plug for the winch. I also used a SimpleAUX kit to make wiring to the lights and relay easier.
Warn 20 foot Quick Connect Cable Kit.
https://smile.amazon.com/gp/product/B00029XFFQ/ref=ox_sc_saved_title_10?smid=ATVPDKIKX0DER&psc=1
Warn 7 foot Quick Connect Cable.
https://smile.amazon.com/gp/product/B00029XEFM/ref=ox_sc_saved_title_1?smid=ATVPDKIKX0DER&psc=1
Warn 2 foot Quick Connect Cable.
https://smile.amazon.com/gp/product/B000CQDQ7Q/ref=ox_sc_saved_title_9?smid=A2TW9PAD7D7YND&psc=1
SimpleAUX
https://badgeglow.com/product/simpleaux/

I searched quite a while, did a lot of measuring and comparing, and finally found a battery box that would attach to the frame behind the right rear wheel. I went with a 34M Marine style (deep-cycle) AGM battery that is intended for draining and recharging (which regular automotive batteries are not), and fits snug inside the battery box. I used the two 10mm bolts left over from the front receiver install to attach the battery box to the bolt holes already in the frame, with some fender washers behind to level it out. I used a nutsert to add another 10mm bolt and strap for additional support, and some 3/8" hardware to secure it.
Battery Box
https://smile.amazon.com/gp/product/B00YI409KA/ref=ox_sc_saved_title_2?smid=A121FQFKA3LNQJ&psc=1
Nutsert Kit
https://smile.amazon.com/gp/product/B07CMNL649/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Battery
https://www.samsclub.com/p/duracell...ize-sl34magm/prod3590225?xid=plp_product_1_19

I'll update with photos when the weather warms up and I get everything connected. I'm going to add a voltage monitor and boost button, so I'll also update with the parts used for that.

 

[WhatExit?]

My plan was to provide a separate battery to power the winch and lights, and possibly other items in the future. I didn't want issues with running the main battery too low, but wasn't willing to put out the $1200 for the Genesis kit and two new batteries. I also didn't really like the idea of removing the ESS battery from the system. I decided to try something a little more flexible, and hopefully less expensive.

The 'brains' of the setup is the Cole Hersee Smart Isolator. It allows front and rear batteries to be charged, use of both batteries for accessories, and prevents the main battery from being discharged too low to start the truck. Genesis uses a version of this in their dual battery kit. They even sell a model of their G Screen to work with this isolator.
Cole Hersee Smart Isolator
https://smile.amazon.com/gp/product/B00LMGPHW2/ref=ox_sc_saved_title_4?smid=A6AY1HFZHO49U&psc=1
Smart Isolator Wiring Diagram
https://m.littelfuse.com/~/media/co...lfuse-if-161-48525-smart-battery-isolator.pdf
Genesis G Screen
https://www.genesisoffroad.com/Genesis-Offroad-G-Screen-p/140-gs.htm

I used Warn cables with Quick Connect Plugs to power my winch, which is installed on a removable front receiver mount. They sell a cable kit (20 and 24 foot long) to put a Quick Plug at the rear of the vehicle. I'm using one of these to connect the battery in the rear box to the Smart Isolator and Winch in the front. The short version (usually attached to a winch) is connected to the rear battery, and the 7 foot version (used to provide a Quick Plug at the front) could also be used to connect to the rear battery and provide a Quick Plug at the hitch. I'm using the relay that comes in the long cable kit with an AUX button to control power to the Quick Plug for the winch. I also used a SimpleAUX kit to make wiring to the lights and relay easier.
Warn 20 foot Quick Connect Cable Kit.
https://smile.amazon.com/gp/product/B00029XFFQ/ref=ox_sc_saved_title_10?smid=ATVPDKIKX0DER&psc=1
Warn 7 foot Quick Connect Cable.
https://smile.amazon.com/gp/product/B00029XEFM/ref=ox_sc_saved_title_1?smid=ATVPDKIKX0DER&psc=1
Warn 2 foot Quick Connect Cable.
https://smile.amazon.com/gp/product/B000CQDQ7Q/ref=ox_sc_saved_title_9?smid=A2TW9PAD7D7YND&psc=1
SimpleAUX
https://badgeglow.com/product/simpleaux/

I searched quite a while, did a lot of measuring and comparing, and finally found a battery box that would attach to the frame behind the right rear wheel. I went with a 34M Marine style (deep-cycle) AGM battery that is intended for draining and recharging (which regular automotive batteries are not), and fits snug inside the battery box. I used the two 10mm bolts left over from the front receiver install to attach the battery box to the bolt holes already in the frame, with some fender washers behind to level it out. I used a nutsert to add another 10mm bolt and strap for additional support, and some 3/8" hardware to secure it.
Battery Box
https://smile.amazon.com/gp/product/B00YI409KA/ref=ox_sc_saved_title_2?smid=A121FQFKA3LNQJ&psc=1
Nutsert Kit
https://smile.amazon.com/gp/product/B07CMNL649/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Battery
https://www.samsclub.com/p/duracell...ize-sl34magm/prod3590225?xid=plp_product_1_19

I'll update with photos when the weather warms up and I get everything connected. I'm going to add a voltage monitor and boost button, so I'll also update with the parts used for that.

I wish I could give you and your post 10 Likes thanks for posting this info with all the details and LINKS! Great stuff for sure.

Please do provide updates and more pics - I'm VERY interested in understanding/seeing how you installed the battery box under the Gladiator. And what's a "boost button?"

 

[Mr._Bill]

I wish I could give you and your post 10 Likes thanks for posting this info with all the details and LINKS! Great stuff for sure.

Please do provide updates and more pics - I'm VERY interested in understanding/seeing how you installed the battery box under the Gladiator. And what's a "boost button?"

The 'Boost' button allows for the Isolator function to be overridden and ties the two batteries together for 60 seconds. Essentially, a built-in jump starter if the primary battery gets discharged too low to start the engine.

Under normal operation, the isolator monitors the voltage and keeps the auxiliary battery disconnected from the system until the primary battery is charged. It then lets the juice flow to charge the auxiliary battery. After both are charged, it parallels them together increasing the available capacity. When the voltage drops to a certain level, it isolates the batteries so they both don't become discharged. The loads (lights, inverter, etc.) will operate until the battery they are connected to is discharged, or the device(s) turn off from a low voltage condition. If the loads were connected to the auxiliary battery, the primary battery is available to start the engine and begin the charging process. If the loads were connected to the primary battery, the boost feature can be activated to start the engine using the auxiliary battery. Using relays allows the loads to be powered by the auxiliary battery, but still be triggered by the AUX switches. Without using relays, all loads tied to the AUX switches are powered by the primary battery.

 

[Oscar Indy]

Great idea.... but isnt there a spot midship that would tuck higher. Like passenger side of the driveshaft? Im fairly sure I'd destroy that box in that location.

 

[Mr._Bill]

Great idea.... but isnt there a spot midship that would tuck higher. Like passenger side of the driveshaft? Im fairly sure I'd destroy that box in that location.

The bottom of the battery box sits higher than the spare tire and the hitch. There's really no other easily accessible place to put it. If you're doing things with your truck that would destroy the box in that location, then the Genesis Dual Battery kit would be a better option.

 

[WhatExit?]

Bill, I'm curious - where did you run the cables from under the hood to the battery box? Got any pics of the underside?

 

[Mr._Bill]

Bill, I'm curious - where did you run the cables from under the hood to the battery box? Got any pics of the underside?

I'll take some pictures when I start working on it again. The cable runs behind the fender liner, with the factory wiring, and down across the top of the frame rail. It goes over the back corner of the fuel tank and follows the brake lines around and then across the top of the frame behind the rear wheel. The wiring kit comes with about a dozen huge zip ties that made it easy to secure the wiring to the frame rail.

 

[Blade1668]

Mr Bill
As I read this I started thinking about the setup I had in my XJ. It was very similar I was using the older Tec for battery splitting the (finned blue one) my second battery was in right rear end of XJ in the cubby hole. Warn winch power cable for winches and the cutoff. I had to "pop" the hood and have a duel battery switch for battery selection. But I did it back 20 years ago so nice update on available new tec. No canbus then.

 

[JoseQ_80]

Excellent work, any update on this project?

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