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Dual Battery Systems?
- Thread starter Buffa
- Start date
You are correct. The Red Arc will charge the aux battery to full charge but your starting battery will not unless you get the truck reprogrammed to increase the alternator output to 14+. The truck charges the starting battery and the Red Arc charges the aux battery.
I'm currently running dual AGM batteries with the Red Arc. I have a battery tender mounted to the truck and plug it in at least once a week to fully charge my staring battery. The program to increase alternator output wasn't an option when I installed the dual batteries last summer. I'm on the fence about getting it since everything I have now is working fine.
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One reason Im getting the OV Tune is so I can get rid of the RedArc unit and just charge everything from the alternator. Reduces the wiring I have under the hood and since Im getting the 3rd Gen Toyota Tacoma (2016-present) VSS System™ - 85 Watt Hood Solar Panel at some point, that can charge the secondary battery when Im camping, hopefully I wont need the redarc anymore.
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Much less a lean issue than a weak subframe issue. The supports for the battery area are weak as hell on the 3rd gens and tend to buckle and crack. Fixing it is a pita. Found out the hard way with my genesis kit putting too much weight in one place.
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Would it be possible for that solar panel to be wired to both batteries with their controller? Reason I ask is a dual battery setup with a blue sea and then topping off both batteries with the vehicle off would be sweet.
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There sure is. But I’m just going to wire the solar panel to my back up battery, and if I need to charge the main battery, I will just connect them together with the isolator
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I am working on a really cool dual battery set-up now. I am installing the Aux battery behind the rear, driver side, seat. I am using the Renogy DC to DC 50a charge controller with MPPT. I will post some pics later.
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Cleaned it up a little bit. Also, I got to test everything out on an 8 night camping trip. We were moving around daily and the longest the system sat without charging was probably 20hrs, but my new battery never dropped below 12.7V and the charge controller cycled from boost to float appropriately. At this point I don't think I will need solar unless I plan to stay in 1 spot for more than 4 or 5 days without running the truck.
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I got about $900 in mine and almost double the AH capacity as the typical AGM, under the hood set-ups that most people do.
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Should be ok for what you want it for. To my understanding a BMS is a solenoid but with the ability to regulate and control. When running more power consuming stuff, the benefit is that it can shut it off more abruptly and save your stuff compared to just the solenoid.
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I agree with @bonifacio with the addition that if you plan on running an AGM as your secondary battery, make sure your alternator is set to charge at a higher voltage (OV Tune can do this) otherwise, your alternator will never fully or affectively charge an AGM battery.
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Trying to learn a bit more about 12v, is the charging voltage specific to AGM? What about LiPo? I know nothing about dual batteries are cheap, but looking at minimal intrusion into factory parts.
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so, yes and no... 3rd gen Tacoma alternators are set from the factory to charge a standard lead-acid battery. Most Lithium and AGM batteries require 14.4-14.8V to achieve an ideal bulk charge and our alternators will typically only produce about 13.8V. You can get an OV tune and ask the tuner to up the voltage of your alternator to accommodate an AGM or lithium battery or you can get a DC-DC charge controller to properly charge and isolate your secondary battery.
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Awesome, this is what I was looking at. Will be a while before I take that leap, but might as well start planning early eh.
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Finally ordered an offgrid engineering dual setup last week. Hopefully it shows up! I also ordered a cascadian4x4 hood solar panel to hook up to my secondary agm. Should be good for the light stuff I’ll power here and there.
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Curious to see how you like that hood solar panel! Been eyeing those lately for a nice additional 80W
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Quick question. Can I repurpose jumper cables to wire in a second battery in the front of the bed instead of under the hood? They're 4AWG so that should be fine, right? They're braided copper and in good shape. I've never done auto wiring with this kind of amperage so I want to make sure I'm not missing something.
The reason for this is the damage some folks have seen from engine bay-mounted secondary batteries, and I'm going to make a drawer system in the bed so I'll have more room there anyway. Plus, that's where all the loads that I'm planning to put on the secondary battery will be so it makes sense to me.
The reason for this is the damage some folks have seen from engine bay-mounted secondary batteries, and I'm going to make a drawer system in the bed so I'll have more room there anyway. Plus, that's where all the loads that I'm planning to put on the secondary battery will be so it makes sense to me.
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Yeah I have a larger hood wrap/decal it fits in the center of really well. Haven’t mounted it yet.
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Just be sure to have a good set of terminals and keep it away from everything. What else are you using with the setup? Guess cut in a solenoid or some type of management.
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It'll be mostly low wattage things, like interior lights, fan, USB chargers. But I also want to put an air compressor back there. I ordered a Viair 88P to start, which apparently draws 20A. I'm not planning on exceeding that amperage, aside from maybe when the alternator is charging the secondary battery. I'll attempt to hard mount it if it works well for me. I have no plans for a fridge or strong exterior lights.
I'm planning to use a solenoid for the price savings, but I'm also worried about stock charging voltage with non-flooded batteries.
Clearly I'm still working stuff out. Thanks for the help
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Awesome. That’s what I would like to do. Do you know what dimension battery would fit and still allow the seat to work after removing the back wall plastic?
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So the point of a second battery is to power loads when the engine is off. So you'd want a deep-cycle battery for that. At that point, the point of having the Redarc charger is to charge up the battery from a depleted state, like if you ran a fridge overnight or for a weekend without starting the car. It will need a charger like the Redarc to appropriately charge it up from that depleted state. Charging a deep-cycle battery is different than charging a starter battery. Though I know that doesn't represent the majority opinion here. Even if you up the voltage for your alternator, you'll still want the charger to manage charging the second battery after it's been depleted. If you're using a starter battery for those loads, it won't last as long because starter batteries aren't designed for loads when the engine is off.
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