Switch's dual battery setup

Now that I've done most of my top priority upgrades, I thought it would be great to add a dual battery to my 2022 Tacoma.

This project started 15 years ago when I did my .

Since I am repurposing most of the parts from my '06 I'd refer you back to that post for more background info.

On my '06 I used the space next to the main fuse block but there is not enough space on the 2022 Taco in that location for a battery. I used that location for a 6 fuse/relay fuse block instead.

I did find a space next to the air intake box on the passenger side.


In the photo above, you will see that I already stacked a pair of hex nut spacers on the top machine screw in that location.

Next step: Cardboard mock up


In this project I found it useful to make a plexiglass mock up to help me see what was going on underneath the battery mount



I got a piece of 1/8" galvanized steel plate from a local scrap yard and cut it to shape:


I was concerned about the weight of the battery on the top attachment machine screw since it was obviously not engineered for that purpose. So I added a weight bearing spacer:





Here the mounting plate is installed.


I mounted the Hellroaring battery isolator on some ABS plastic I had on hand



So the (almost completed) project looks like this:


The ABS plastic that holds the Hellroaring battery isolator is on top of a 1/4" aluminum plate that was also salvaged from my 06' project.

The battery is an

$255 ODYSSEY ODYSSEYODYODS-AGM28L

Odyssey PC 925

The switch to use the backup battery is located in my dash and labeled "Power".


The dash switch mount is from Fitzaprint on Etsy
The switches are sold by

$24 CH4X4 Push Switch for Toyota Tacoma, FJ Cruiser, Land Cruiser, Fortuner, Hilux, 4Runner, Prado 12V 3Amp - Power Symbol 2 - Blue LED

CH4X4 on Amazon.

Finished setup

 

Nice work now, why the second battery ?

 

Here's what ChatGPT had to say:




Installing a second battery in your off-road truck can provide several benefits. Here are a few reasons why you might want to consider adding a second battery:

1. Power for accessories: Off-road vehicles often have a variety of accessories that require power, such as winches, lights, and air compressors. Adding a second battery can provide extra power for these accessories, ensuring that they don't drain your primary battery.
   
   
2. Backup power: If your primary battery fails, having a second battery can provide a backup power source. This can be particularly important if you're offroading in remote locations where getting a replacement battery may be difficult.
   
   
3. Increased capacity: By adding a second battery, you can increase your overall battery capacity. This can be particularly useful if you have a lot of power-hungry accessories or if you need to run your vehicle's electrical systems for an extended period of time.
   
   
4. Improved performance: A second battery can also help improve your vehicle's performance. By providing additional power to the starter motor, you can improve your vehicle's cranking speed and make it easier to start in cold weather or other challenging conditions.
   

Overall, adding a second battery can provide a number of benefits for off-road enthusiasts. However, it's important to make sure that your vehicle's electrical system is properly set up to handle the additional battery, and that you use high-quality components to ensure reliable performance.


I was mostly focused on item #2, since I already replaced my main battery with an Odyssey PC1700 deep cycle battery. But it does increase capacity by about 50%.

 

Very nice batteries! Love my dual battery odyssey with redarc setup. I recently added solar connections

 

#2 is probably the most important reason for having a second battery, being able to jump yourself with a jump pack or a battery is essential for solo off-roading.

 

@CLVol1255
What are the two cables leaving the passenger fender going across the air intake for?

 

I guess I was not completely finished with this installation. I wanted to add voltage meters for both the main battery and the axillary battery.

Here the led light indicates that the Hellroaring battery is working. And the two voltage indicators are for the main and auxiliary battery respectively.


Maybe mount below the dash next to the cup holders.

I don't need switches in this location but it made sense to explore the possibilities. Or a cell phone or map pocket?

5 Switch version



Or open for a cell phone.


The main part conforms to the center console. I made it so the face plate can be changed to other displays/ switches:


Face plate and length of the pocket can be modified to need:




Need to move the LED light

 

Still chipping away at the design for the LED voltage displays. I have switch positions available to the left of the steering wheel but I think it makes more sense to concentrate gages and a switch for the aux battery in one location. I also realized I have room for a third voltage display - like for my solar panel!

So my current design has an LED light for the Hell Roaring battery isolator, three voltage indicators for OEM battery, Aux Battery, and Solar Panel, plus the switch to connect the Aux battery if needed. And a slot for my iPhone. Now I have to wait two weeks for a third LED voltage display. But I can get everything wired up...

 

That’s my 50amp Anderson plug connector that runs to my solar panels

 

I finally got around to completing the Aux battery switch, LED, and voltage displays. Something about the camera I used makes the digits appear a bit washed out but the voltage readings are very clear to the naked eye.

 

Isn't it a little sketchy having those terminals so close to the hood latch?

 

They’ve got a good 2 and half inches of clearance or more and it’s been trouble free for 3 years now. Even if I rear ended somebody everything is fused. At the terminals and at the red arc bcdc charger

 

Does the second battery charge in parallel with the primary battery from the alternator? Is it a concern to have two different batteries charging like that? I would like to do something similar, but can't find the space for another full size battery.

 

That question would be better to ask Hellroaring (who made my battery isolator) but I can say that I never had any problems on my 06 Taco and I had the setup for 16 years.

 

Good stuff!