Adding an Auxiliary Battery

[RAM Patriot]

Replaced Batteries with a set of Super Start Platinum AGM Top Post Battery Group Size 94R H7 - 94RPLT from O'Reilly Auto Parts.

The truck is a 2019 model and still had the original lead-acid starter battery from the factory. I was noticing that the battery was getting weak and decided it was time to replace before it failed.

I went ahead and bought two since I was switching to an AGM battery which has a lower internal resistance and better voltage output then the lead-acid batteries.

 

[Bigty]

If you have a lead acid battery or AGM as your starter battery I would purchase an auxiliary battery that is the same type of battery and cranking amperage to help with the charging profile.

Lithium battery manufacturers recommend specialized lithium battery chargers for optimal performance.

When I setup my auxiliary battery I used the REDARC Smart Start SBI12, which is a 100A 12V battery isolator which protects the start battery from excessive discharge, while allowing the auxiliary battery to supply charge to non-essential loads.

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Is that a 2500 Battery Box? I just did the Mopar CAI, so i have space. And Damn that thing is CLEAN!!

 

[RAM Patriot]

Is that a 2500 Battery Box? I just did the Mopar CAI, so i have space. And Damn that thing is CLEAN!!

Yes, I had to retro fit a battery tray from a 2500.

Unfortunately the battery tray for the 2500 will not mount directly into the wheel well on the passenger side of the 1500.

The mounting holes are in different locations and it does not follow the wheel well liner that also mounts to the intake box to hold the liners in place.

I had to fabricate the Mopar 2500 Passenger Side (Right) Battery Tray - Mopar (68350658AC).

The first thing that I had to do was cut off the bottom hangers from the battery tray since they did not have a place to mount to the frame and they were in the way for setting the tray on the wheel well liner.

The next step was to sit the tray down in the wheel well and see how it lined up.

After sitting the tray down in the wheel well. I had several more challenges:

1. The wheel well holes did not line up with the holes in the bottom of the battery tray.
2. The front bottom of the battery tray did not touch the bottom of the wheel well.
3. The hood shock is hitting the lip of the top battery bracket.

So back to the work bench for another round of cutting and some fabrications.

Cut the top hanger from the battery tray. (I had to add a T-Strap)

The next step was to add a heel to the front bottom part of the tray so that it would sit on the wheel well and allow me to drill a hole for the wheel well screw.

I had a 3/4 in. Schedule 40 PVC Type-T Conduit Body on the shelf left over from a wiring project and it happen to be the perfect size.
Mixed up some J-B Weld and the next day it was ready to go.

I also should mention that I had to cut off the wheel well factory towers that lined up with the 2500 so that the battery tray would sit flat on the back part of the wheel well.

Since I lost the top battery bracket I had to fabricate a T-Strap to work to hold the top part of the battery tray. Lined it up with the factory hole on the frame. drilled a hole in the tray for the bottom of the T-Strap and bolted it on.
Used a 6 in. x 5 in. 14-Gauge Galvanized T Strap

I had to drill two holes for the front brackets to the frame. Used the factory bolts that I took from the air filter tray.
The factory bolts are: M8. 1.0
I used a Drill Bit: 1/4”
Then used a Tap thread bolt M8. 1.0

Drilled some holes in the bottom of the tray and put the factory wheel well screws back in.
Installed the Battery Tray.

Then I installed the Mopar Battery that is the same as the factory starter battery for matching the charging profile.

 

[fugarrr]

IMHO probably. I have 2 x 100Ah LiFePO4 batteries, and I unload them after each road trip. I have a fiberglass topper on my bed, and during the days right now, the outside air temps hit the mid 70's, but inside the sealed up topper + bed, it's hitting close to 120F. Most of the these batteries have a max temp spec in the 120-150F range. During road trips, the batteries are buried under a lot of other junk, which seems to help them stay relatively cooler. I also tend to be driving during the day on road trips, so I suspect that helps cool the back a bit as well, even without open windows. I would definitely keep Li* out of the engine bay. The couple times this winter (SoCal) that I polled the IBS temp after driving around short distances, I got back about 125F.

I agree..