Dual Battery Setups! Let's see them! Multiple Batteries Thread!

No they don't need to be charged at the same time. If you can keep up with keeping the 2nd battery topped off then by all means go your way. It just really makes no sense, you have no advantage to doing it your way. 150A continuous duty solenoids are very cheap and simple devices.

 

link me to one please.

My experience with solenoids (on boats and in my lab), is that if the power source for the solenoid goes out you are screwed. Unless it is one that you can switch with a screwdriver or a manual override switch. It they over heat you are screwed. It they get wet you are screwed. But i am considering it. It would be nice to just have a rocker or toggle switch on the dash board. It is just more moving parts to deal with and more things to go wrong. I have had many experiments (I am an aquatic toxicologist) fail because 3 months into a project an expensive solenoid fails and all my fish die. And those are expensive waterproof science grade components. Not much can go wrong on that big red marine switch.

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But then again, i have others that kick on and off every few seconds and have done so for >15 years.

 

This seems like a really good, simple solution. One wire to the on/off switch, one wire away.

 

It is. Just get a switch that can handle at least 700 amps momentarily because, should the primary battery go completely dead, the starter will be drawing power from the aux battery. And don't skimp out on the ground wiring for the aux battery - wiring between the neg posts should be 2AWG, minimum; the engine block and chassis ground wiring can be 4AWG.

And to affordably monitor voltage of the aux battery, connect a fuse-protected power outlet and install a low budget voltage meter.

 

Hey guys I have a battery question. I tested the resting voltage of my primary battery and it was 12.01 volts. Shouldn't I be seeing 12.4-6? I've only been driving for ten minutes a day if that matters.

 

12.6 volts is ideal for a sitting battery and fully charged. The 10-minute a day driving is killing it. The alternator is not given enough time to recharge the battery.

Here are some options:
Double the driving time to give the alternator time to charge the battery.
Connect a trickle charger overnight. A model with quick disconnect cables may suit your needs.
Install a trickle solar panel. Connects to cig lighter, but may not be enough for your needs.
Install a high output alternator - it will have a smaller pulley and spin faster at lower RPMs. This is what I did for my daughter's Corolla when she was going to high school; her commute was 4 miles each way.

 

Thanks chuy I just walked back inside after destroying my shin on the BBQ. Not yo ur fualt i didnt see this post til now.I hooked up.a high quality multi stage charger so I'll report back in the morning.

 

You'll want to use a low amp charger (<4 amps). Too many amps may cause the battery acid to bubble it's way out of the battery, depleting the fluid and/or corroding whatever metal it comes in contact with. If you use a higher amp charger, it will be best to remove battery from the car and place it on a board and check fluid levels before installing. I suppose you'll be OK if you have a sealed AGM battery or similar - I don't have experience charging sealed batteries.

 

I'm using a low amp (1) multistage charger by yuasa, I've used it on my motorbike and atvs for years

 

I'll be interested to see if that's enough. A 1-amp might fall into the 'maintainer' vs charger category. Keep us posted; I'll be shopping for a trickle charge soon myself. I have a smart charger but it's too expensive to outside overnight.

 

The charger is 1A 3 stage, cheap but has worked very well on my atv and generator batteries. I will be leaving it on overnight and I have an ultraguage that shows voltage to .01 the charger is quite hot already.

$80 Yuasa (YUA1201000) 1A Automatic Battery Charger and Maintainer

https://www.amazon.com/Yuasa-YUA1201000-Automatic-Battery-Maintainer/dp/B00HZTDKZG

 

I have a 2nd gen RC, so this may not help Cadmus's case, but thought it was worth mentioning that I was successful in running a single 4AWG welding wire from my battery, through the firewall, and to a 300 amp switch in the cab. All wires are hidden and the switch is mounted through the center console under the shifter. It has a detachable key that is kept in the glove compartment. I did this several years ago to hook up a 700 watt inverter located under my seat.

It's a little different scenario because Cadmus will need thicker wire and to make a second run through the firewall (if following Chuy's suggestion). The 4AWG wire I used made things pretty tight where the existing wiring harness runs through the firewall.

 

Thanks.
It is tempting, lots of space on the center console and easy access. I am pretty weary of having that much juice in the cab. This morning, the firewall looked more crowded than i assumed .
Honest... i recant slightly....i am considering the solenoids now. For safety reasons.
A simple on/off for bat 1 and an on/off for batt 2. only IF i can find an affordable one with a manual override option and sadly i am having little luck.

And Nice Avatar @ecoterragaia.

 

You could use a solar charger to maintain the battery and an appropriate power supply. I actually came up with a dc-dc charging idea for a trailer project I was working on. Here is a link to the post: https://www.tacomaworld.com/threads/making-a-dc-dc-battery-charger-for-less-than-25.450892/

 

Update , you were correct. At least in my case, the 1A charger was not enough to get to float even after 12 hrs. I drove the truck for an hour and my resting volts returned to a healthy level. The charger I think is suited better for smaller batteries, such as in my atv and small displacement generators and the like.

 

Good to know. I've been looking at 3-4 amp chargers. Price-wise, I like the new Energizer ENC4A, a 4amp smart charger for $30 - has no optional accessories. At the top end of trickle chargers, I like the Noco G3500 and CTEK 3300 - 3.5 and 3.3 amps, respectfully; both average about $60, and both have a myriad of optional accessories.

 

Hello forum,

I just finished installing the Armor Tech Offroad (ATO) Dual Battery Tray for two Optima Group 34 Batteries and thought I'd share some notes from the experience...


First of all, the pieces from ATO are beautifully cut (water jet?) and precision bent - fit and finish was great (well, small problem with fit, but more on that in a moment) and I had a couple questions and the guys there were super friendly. Would heartily recommend this product, and ATO as a business from that interaction.

One minor issue out of the box is that (as with seemingly all aftermarket stuff) all the fasteners are imperial. Needless to say, i've given up on trying to keep the truck metric, but this will continue to bother me. The hardware kit also came with these long self-drilling/tapping sheetmetal screws, but the battery stands on a little shelf welded to the fender and it's not long enough to take that whole screw body... and i own a drill... so I replaced them:


I am not the most patient guy so I planned ahead and painted up the parts well in advance of when I was going to have time to do the install so i wouldn't be tempted to jam them in there still tacky. There is a bottom plate that goes in with standoffs that attach the actual battery tray. You kind of have to eye-ball the fitment and I didn't do a great job with this the first time... There's a single bolt that locates the center forward corner of the tray down low against the fender. But then you have to eyeball the tray to make sure it's parallel to the fuse box, but i found that dead parallel caused interference with between the battery and the headlight. Sadly, i found this out *after* drilling the first set of holes. I also found that the rear out-board tab that holds the battery was a little too tall to not hit the fuse box, so it had to be slightly trimmed, and the plate interfered with the original battery hold-down tab. So that also meant a little grinding.


So much for nice hard paint...


If you look closely in the image you can now see the rear-most tab is a little shorter and tucks in line with the face of the fuse box. ATO's instructions say to remove the little tab on the lid of the fuse box directly above the plate's tab, but i found that to be unnecessary. Also, you might be able to see already how incredibly tight it is going to be up against the headlight, and the main wiring harness entering the lower corner of the fuse box. Last thing, I also had to do a very gentle bend of the aluminum pipe coming off the radiator (or heater core?). Eek. Everything tightened down with Loctite, time for batteries and wires.

The battery install is part of a larger plan for this truck that will involve radios, lights, and the like, and I'd been looking for a good installer to do the wiring for me. A friend in the emergency services world suggested some "tips" for figuring out if the installer is good. Do they use thin-wall insulation wire, wrapped in a loom? water proof connectors? heat shrink? solder or crimp? Etc etc. This is one of those areas where i definitely would err towards buying the best, cry once. I was pointed to Santa Rosa Cartronics (for those of you in the north bay area) and was really impressed with the quote - expensive, but doing all the right things. I got my two Optimas from them, and they whipped up some temporary interconnect cables - pretty nice work:


When i get the lights, radios and power distribution ideas all sorted, I'll be back to have them do the "grand wiring."

Here it is all installed.


You'll notice the outboard battery is basically touching the back of the headlight. Hopefully that doesn't cause problems in the future. I'll have to remove a battery to change the bulb, but I think that's the only practical downside to locating the batteries here.

The positive terminal is now a janky mess, but hopefully i'll have this in at SR Cartronics soon to have that all cleaned up. Planning on a BlueSea ML-ACR, solar charger, house/main battery selectors for various systems... Gonna be fun. Here's a little teaser of where i plan to put some of this stuff:


Time to go bend some sheetmetal!

 

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Did you ever route that hose anywhere? I am in the minority as you are with the ABS module on the fender. I'm torn with going this way or relocating the power steering reservoir. My only concern with the different hose would be passing smog. Have you re-smoged with that different hose on? SMOG guys can be sticklers for any little thing that isn't 100% stock on the air system.

 

Kinda hard to see in the pic, but air duct faces down at the bottom of the pic. I zip tied it to the upper rad hose. I hear you about CA being sticklers with OEM emissions. My smog is due next year and I'm prepared to remove aux battery and re-install the OEM air duct system. Should only take 10 minutes max, then I'm good for two more years.