Ideas for PORTABLE dual battery/inverter setup I can use in different vehicles? (1 Viewer)

[IdahoDoug]

So, I have three vehicles we routinely use for camping and travel - our LandCruiser wagon, our trailerable powerboat, and a Vanagon. For years, I've used a simple system to provide house power which I move from vehicle to vehicle as needed. It's a standalone RV deep cycle battery, an inverter plugged into it, and a power cord also connected to the battery for a cigarette lighter type outlet. We routinely charge flashlights, cell phones, laptops and a fan for hot summer nights. When sleeping in the Cruiser for instance, I park the battery in the center rear footwell with a fabric cover, and the inverter and DC outlets are laying next it it for use in these tasks as needed. On a week trip the battery holds enough energy for all our needs and we've never run one dead a single time. I've just upped my game for backcountry access with a new state of the art battery powered chainsaw and began contemplating how I'd charge it in the field. It's an Echo 56V with a 5ah battery. I'd probably want now to connect this battery to the alternator, and perhaps also the inverter (would like to get a new larger one as part of this project). So, any ideas on a simple system to accomplish this? I'm thinking it would for the first time connect my house battery to the alternator, and an upgraded inverter and I guess I'd need a simple charge manager to split the charge between this house battery and the underhood one? For guidance, I'm not interested in a massive system like some of you guys have with super pricey state of the art charge managers, etc. I'm envisioning a piece of plywood with the inverter bolted to it, and the charge manager (if needed), and also the board would have a cord winding system where I can carry it to the other vehicle, unwind cords to connect with quality underhood battery alligator clips, etc. No interest in solar, as we live up north and some of our trips are winter where solar is paltry. Thoughts?

 

[gummycarbs]

4 gauge cable from the main battery to the cargo area, using a Maxi Fuse at the battery and an Anderson PowerPole connector in the cargo area. Put the house battery and inverter in a box, like a Pelican case or RV battery box, along with a battery isolator, and a short lead to another Anderson PowerPole. The inverter would be wired to the battery in the box, and the isolator connect it to the PowerPole feed (i.e. main battery) when the main voltage goes over 13V or whatever.

I wouldn't incorporate any extra cord into the box. Make an extension cable that uses PowerPoles if you want. Keep it modular.

This is functionally identical to having dual batteries under the hood, but all the complexity is inside your portable box instead. The only way you're going to get any simpler is to skip any kind of isolator and just remember to manually plug it in after you've started the vehicle and unplug it afterwards.

For the isolator, look at something like a Samlex ACR-160 ($110 - $130ish).

 

[Feistl]

I’ll just add remember that the inverter needs ventilation so be careful having a full sealed box

 

[overpakd]

I know you already have a battery and inverter, but this is exactly the use case for a jackery/bluetti/goal zero/pick-your-brand portable battery system. They come in all sizes, include an inverter and even the huge ones are uber portable. They're all coming down in price and there is plenty of competition with lesser known brands if you want to save another couple bucks. I'm about to install a 100AH lithium and charging system in my 80 because I don't need it to move around, but I currently use a small Jackery to power a fridge, lights, charge phones, etc. and move between 2 vehicles. You can just plug it into the car's cigarette lighter to charge while the vehicle is running. That could be current restricted and take too long to recharge for you, so you could make a dedicated 12V run to the battery for the charging cable if that was better. In my truck, I have a hard line to charge the portable, but in my wife's car, we just use a 12V socket.

 

[BILT4ME]

4 gauge cable from the main battery to the cargo area, using a Maxi Fuse at the battery and an Anderson PowerPole connector in the cargo area. Put the house battery and inverter in a box, like a Pelican case or RV battery box, along with a battery isolator, and a short lead to another Anderson PowerPole. The inverter would be wired to the battery in the box, and the isolator connect it to the PowerPole feed (i.e. main battery) when the main voltage goes over 13V or whatever.

I wouldn't incorporate any extra cord into the box. Make an extension cable that uses PowerPoles if you want. Keep it modular.

This is functionally identical to having dual batteries under the hood, but all the complexity is inside your portable box instead. The only way you're going to get any simpler is to skip any kind of isolator and just remember to manually plug it in after you've started the vehicle and unplug it afterwards.

For the isolator, look at something like a Samlex ACR-160 ($110 - $130ish).

I did something similar.

I have a 3500W pure sine inverter with a 6 ft seat of 0 welding cable and an Anderson connector.
I ran a set of 0 welding cable into the interior of my LC and anchor a mating Anderson connector inside that I can plug in the inverter when needed. This way I can move the inverter to our van when needed, as we have a similar setup on the van. The main purpose of our setup is to charge a power wheelchair when it's with one vehicle or the other.

We use the main battery on each vehicle, not a separate one.

 

[CalnSam]

i use a jackery to charge makita batteries, run the fridge etc. it works really well.

 

[jpoole]

Sounds like you should just upgrade your current battery system with something like one of these:

Amazon product ASIN B09GKCBSV1​

​

Amazon product ASIN B09CK6Y332​

I've purchased both of these pretty recently for different uses and they are on the lower cost per / watt hour end of the spectrum. A few shopping tips:

• Do some simple math to estimate how much you need to run at once and how long you need to power whatever you plug in. If you need to run two laptops for instance go check their power supplies and/or read online to see how many watts they burn when running to make sure the AC outlets/Inverter can run both at the same time. Inverter output are often rated in Watts while capacity on these, on Amazon at least, is often in Watt Hours.
• Once you have a rough ballpark of the output/capacity you need you can start to hone in on how much you want to spend. Prices do vary between the more popular brands and lesser known units.
• Features vary more in the smaller units and essentials are more likely present in the larger units. USB ports, cigarette port, AC outlets, solar/DC charging inlets are pretty standard above a certain size. Digital display of use rate, estimated remaining power, etc. is also pretty standard on most of these.
• Only shop for the LiFePO4 battery based units (my opinion) as they are safer and can be used through many more cycles.
• Setup your cars with a solid DC feed to the LiFePO4 unit you buy so that you can recharge it when running the engine. Solar can easily be added as well.
• "Pass through" charging is when the output ports still work while the battery is being charged. Not all units have this and it may or may not be important to your planned setup.