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Discussion Starter · #1 ·
It is difficult to compare portable power stations as even the technical sections of their websites obfuscate the power output of these devices by reporting its output at 3.6 volts, 120 volts, inverter watts and occasionally as amp hours. If they all reported the internal battery’s output in watts or in amp-hours at 12 volts it would be easy. I’ll use the last in my posts. Hidden in the specification sheet is also the battery type. AGM lead acid batteries are heavy and cheap. Lithium Ion batteries are lighter and more costly but with comparable recharge life. LiFePO batteries are expensive, long lived, safe, and expensive. All these power stations have some common features. Most include USB charging ports, one cigar type outlet, several SAE or other output ports, a solar controller and an inverter.
I settled on building a lithium based 50 A-H storage unit which is size comparable with a $2,000 Jackery or Goal Zero. For my needs I decided to have the inverter plug in but I could have had it inside, same for the charger. Both will fit into my box if I want them along. Here is the finished product:
Machine
Technology Wire Electronics Electronic device


Here are the products and costs:
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I picked the battery first. AIMS is a well known lithium battery producer and it has available 50 A-H or 100A-H. I looked at my needs which as to mainly run a small chest refrigerator and felt the 18 pound 50 A-H was sufficient. If 100 A-H was chosen most of the other components and fuses would need a slight upgrade. The LiFePO battery is limited to 50 amps output and charging rates should be 5-10 Amps. Since I wanted a complete system I also bought a 100 watt solar panel. I found a lithium specific charger for home use and cables for the vehicle cigar lighter socket to charge it as well. Renogy makes several 10 amp solar controllers and the new model Voyager has a wake up feature if the battery’s BCM has shut it down. My lithium smart charger can do that as well.
Amazon provided lots of ports for input and output, a fuse panel with 6 connectors and a negative buss, USB and cigar outlet and others. The box is a cheap Home Depot “Homer” toolbox but any 16"-20” toolbox would work. I had the 19” one already saving $10. Super waterproof cases by Pelican and others might be nice but are not necessary and sizing just what you need may be tough.
The next step was to fit everything inside. I laid the battery on its side on a plastic block that supported it and left lots of air circulation. I then mounted the positive fuse panel, the negative buss, the solar controller (outside as it is waterproof) the very cool AiLi battery monitor and the main fuse block. Once they were attached I wired them up just like you would in your van- Battery positive to main disconnect to main fuse to fuses block then negative to the monitor’s shunt to negative buss bar. The solar inputs are Anderson Powerpole to the solar controller then to the positive fuse panel, the USB and cigar outputs to the fuse panel and two SAE input/output ports that the chargers use. Here are internal pictures of it wired:
Technology Electronic device Electronics Vehicle Auto part
Electronics Technology Battery charger Electronic device Auto part
Wire Electronics Electrical wiring Technology Electronic device

There is a cover for all that:
Trunk Vehicle Suitcase City car

My final thoughts:
This will supply as much power as a 100 A-H lead acid battery. It runs my refrigerator for about 4 days. It weighs about 23 pounds and carries easily. The solar panel will charge it up to full from 50% SOC in 3 hours or a similar time with the 110V charger. I haven’t yet used the car charger as this is so easy to keep charged. I could add a second 100 watt panel for faster charging as the double Powerpole port is ready. With the WATTBOX done I have a portable power source for less than $700 which would be $2000 if purchased and it is better being LiFePO instead of Lithium Ion with its shorter life or AGM with its weight. It is customized for my use so I do not have a black box of proprietary parts I depend on some unreliable company to replace. I have an older 350 watt inverter but included the cost of a sine wave new one to be fair. The box has space to cary all the cords, the charger and the inverter which could be installed permanently.
Would this run your van conversion? It could if you did without a microwave and induction cooking or other high draw appliances. Lights, chest refrigerator, electronics charging and other basic needs could be done easily. If you were willing to have a 30+ pound 100 A-H WATTBOX then nearly everything could be done and it could be built for $1200+-
 

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Nice design.... reminds me of some of the Ham Radio Go-Kits I've built. I've used Plano cases for those. In my van, I use Harbor Freight toolboxes for my AGM battery boxes. You get 4 sizes for about $25 - one was just right! and the others are actually used as ..... ..... ..... toolboxes!

Casually looked at the GoalZero stuff... expensive! Your design could be cheaper with AGMs, but more weight to deal with! Portability also solves any freezing issues that built-in would have to deal with.

I often think that I could live without the microwave and induction (just use butane stove for most of it). And it's not an issue if you're at a CG. So, less may be best!
 

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I like it, the beauty of this is, you built it. You know exactly whats in it, and where. Makes repairs on the road much easier & faster.
Runs your chest fridge for 3-4 days pretty cool. If I may ask, whats the current draw of your fridge?
 

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Nice project and looks like it was a lot of fun to put together. But your price comparision ($2,000) is a little high.

A Jackery 500 (43 Amps @ 12v) is $500 and has a MPPT controller (the Renogy controller used in your box is a PWM) from Jackery's site with free shipping. A Goal Zero Yeti 500X (42 Amps @ 12v) is $700. It is also MPPT and includes USB C PD ports, which can charge a modern laptop directly, and also quick charge phones that support it. Both of these units use high-quality parts (teardowns are available on youtube).

The big rip off for those units, and maybe where you get the $2,000 number, is the proprietary solar panels, but you can just buy adapter connectors that adapt proprietary plugs to MC4 and use any panel you'd like. So for each of those, you could use the same 100 watt panel and a ~$25 adapter.

I'd be interested in a long-term review of the Alpicool if you buy it (wasn't sure if you're just showing what's possible or if you actually purchased it).
 

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Discussion Starter · #6 · (Edited)
I have been using all this for nearly two months. The Alpicool is a great frige and the bluetooth is very handy. https://smile.amazon.com/gp/product/B07L3FRDPK/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1
Yes I had the price wrong I see the Jackery 1000 at $999 and it is Lithium Ion (a poorer and cheaper) battery and 13% less power. 46.4 A-H compared to 53.3 A-H for mine.
Jackery’s site says "Larger capacity and higher wattages: 1002Wh(46.4Ah) lithium battery capacity, 1000W Rated Power and 2000W Surge Power."
A Jackery 500 has less than half the power of mine:
From their site: "518Wh(24Ah) lithium battery"
So you see that getting the A-H is the only way to compare!!

BTW a 100 A-H lithium Ion battery is $179 and a 100 A-H LiFePO battery is $799. You get what you pay for unless you build your own then you get what you want for about half and have fun doing it! Jackery’s battery is a $100 battery mine is $399. Goal Zero uses some AGM batteries- heavy and <$90

Last point, PWM is fine for this application, MPPT has its place and I have use both multiple times. I CHOSE PWM for my one hand placed panel.
 

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A Jackery 500 has less than half the power of mine:
From their site: "518Wh(24Ah) lithium battery"
So you see that getting the A-H is the only way to compare!!
They're actually not that far apart, but it's not obvious since Jackery quotes battery capacity in a confusing way.

For the 500, it is 24 A-H @ 21.6 volts. 24 A-H * 21.6 volts = 518.4 watts. For the 1000, it is 46.4 A-H @ 21.6 v. 46.4 * 21.6 = 1002 Watts.

AIMS quotes battery capacity the "normal" way (amps at around 12 volts - 12.8, in their case).

To compare apples to apples, in my initial post, I re-calculated the amp hours of the Jackery at 12 volts, since that is how AIMS quotes battery capacity.

So, my math for the Jackery 500: 518.4 watts / 12 volts = 43.2 A-H. This is ~10 A-H less than the AIMS battery you used, which is 50 A-H @ 12.8 volts = 53.3 A-H @ 12 volts.

The moral of this story is that watt hours is a better way to talk about power station capacity. The RD custom built power station is a 640 watt hour unit, so it falls between a Jackery 1000 and Jackery 500 in capacity. I agree that the AIMS is probably a better battery chemistry, and it is rated for more charge/discharge cycles in it than the Jackery, so one of the wins of a d-i-y powerstation is you get to choose each component.

Sounds like that Alpicool is a nice fridge. Bluetooth would be a nice feature.
 

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Discussion Starter · #8 · (Edited)
Thanks for clarifying. All that being said I could have gone with a Li Ion battery and had my 640 Watt-h WATTBOX for $<400. That would still make it a bargain. Still It seems these things will get to a price point that DIY will cost more than a mass produced item. It should. Without looking at such things one might buy a Goal Zero with a 30 pound AGM battery and useful SOC of 50%!
Things that have worked well is the AiLi meter as it gives SOC directly, shows charge and discharge, and voltage. The AIMS battery was supposed to have an app and bluetooth but it is not enabled on mine. The app for the fridg is very good showing voltage in and temperature but strangely does not show when the compressor is running. It sips power!
 

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Discussion Starter · #9 · (Edited)
Some have asked about the discharge capacity of this sort of LiFePO4 battery box and perhaps a larger one. I considered a 100 Ah version but it’s size and weight brought me to this capacity.
The specifications for my AIMS 50 Ah LiFePO4 battery lists the discharge MAX at 100 amps for 10 seconds and 50 amps continuous. 50 amps at 12 volts is 600 watts so I could run a 600 watt inverter continously. The 100 Ah battery from the same supplier list 200 amps MAX for 10 sec. or 100 amps continuous. That gives one 1200 watts output for an inverter. I’d be conservative and not go quite that far. The charge rates are the same respectfully for the two batteries. I chose to charge mine at only 5 Amps (about 70 watts) whether I do it with my specialized 110 volt charger or my solar panel.
The weight of my 50 Ah unit without a B to B or inverter weighs 24 pounds with a 17.75 pound battery. A 100 Ah WattBox would weigh 38 lbs. with a 30 lbs. battery. I think it would be manageable. Mine feels like a light toolbox as though it was partially filed with tools.
I never did buy the sine wave inverter to instal. For me it is the least useful component of the commercial units. The small output from this battery limits one to low power AC anyway.
 

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Nice work.

Connectors are always an interesting area.

Am I correctly understanding that you are using SAE connectors for 12 volt input and anderson for solar panel input?

IIRC, the goal zero uses SAE connectors for solar input?

I have the tools to crimp anderson connectors but I have resisted using them, because they aren't low temperature rated. People like then though.
 

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Discussion Starter · #11 · (Edited)
Yes I used two SAE connectors fused but directly connected to the battery. I use them for general connections such as charging, and output to some devices I already had similar connectors on.
I did use 2 Anderson Powerpole connectors for the solar as I wanted an incompatible feed to the solar controller to avoid confusing myself. I did that as well because Jackery uses them for their solar input and folding solar panels are often supplied with a cable optioned for them. Mine was:


This is the type of HD SAE connector I used:


A car charging cable was available for that:

Goal Zero seems to use an 5.5*2.1 mm circular plug for its solar. I don't like them for more than 5-8 amps as they are really small and easily damaged IMHO. As for the low temperature rating of Anderson, I can’t charge the AIMS battery below about freezing anyway. I have found the Powerpole connectors to be very good, no exposed electrical active surfaces, positive install on the ends and good feel to indicate they are connected. I did have one that I had not completely installed the metal clip and it failed to connect. I frustrated myself finding why my solar panels wouldn't charge!
 

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Nice project and looks like it was a lot of fun to put together. But your price comparision ($2,000) is a little high.

A Jackery 500 (43 Amps @ 12v) is $500 and has a MPPT controller (the Renogy controller used in your box is a PWM) from Jackery's site with free shipping. A Goal Zero Yeti 500X (42 Amps @ 12v) is $700. It is also MPPT and includes USB C PD ports, which can charge a modern laptop directly, and also quick charge phones that support it. Both of these units use high-quality parts (teardowns are available on youtube).

The big rip off for those units, and maybe where you get the $2,000 number, is the proprietary solar panels, but you can just buy adapter connectors that adapt proprietary plugs to MC4 and use any panel you'd like. So for each of those, you could use the same 100 watt panel and a ~$25 adapter.

I'd be interested in a long-term review of the Alpicool if you buy it (wasn't sure if you're just showing what's possible or if you actually purchased it).
Since a Jackery 500 is part of our hurricane prep kit, we plan to use it as the base power for our 12 volt lights and cooler. Has anyone else gone this route? We do have a NOCO2 installed for shore power.
 

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Discussion Starter · #14 ·
You could, and even a 100 Ah version (functionally equal to about an 180 Ah FLA battery) would still be portable at 38 pounds. First determine if you need that. Keep the maximum amp draw down to something less than 100 amps @ 12 volts for LiFePO4. You can go to much higher discharge rates for Lithium Ion but the longevity will be MUCH less and the cost somewhat less too. Remember no charging below freezing. Few components would need changing, just some wire sizes, fuses, and solar controller.
 

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You could, and even a 100 Ah version (functionally equal to about an 180 Ah FLA battery) would still be portable at 38 pounds. First determine if you need that. Keep the maximum amp draw down to something less than 100 amps @ 12 volts for LiFePO4. You can go to much higher discharge rates for Lithium Ion but the longevity will be MUCH less and the cost somewhat less too. Remember no charging below freezing. Few components would need changing, just some wire sizes, fuses, and solar controller.
Honestly, AGM has me thinking. I just can't justify 4x the cost for lithium. We won't be living in it permenently, just using for short trips, weekend trips, extdwnded trips, track days (towing vehicle) etc
 

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Discussion Starter · #16 ·
If it is staying in the van then I agree wholeheartedly. I’d go for 2- 6volt FLA golf cart batteries in series. They are rugged, last nearly forever, cost less than $200 total, are easy to charge, give you 215-230 Ah and only need a bit of distilled water once a year? For your use why pay twice as much for AGM?
Think Sam’s Club or Costco.
 

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If it is staying in the van then I agree wholeheartedly. I’d go for 2- 6volt FLA golf cart batteries in series. They are rugged, last nearly forever, cost less than $200 total, are easy to charge, give you 215-230 Ah and only need a bit of distilled water once a year? For your use why pay twice as much for AGM?
Think Sam’s Club or Costco.
Because carrying distilled water is extra space? I'm not sure, but less maintenance is more in the long run, no?
 

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For example:

 

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For example:

And, triple the cost of flooded 6 volt golf carts with no more power. I haven't added any water to my 2 - 6v GC's in a year so carrying around distilled water isn't too much of a burden (for me)🙄
 

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And, triple the cost of flooded 6 volt golf carts with no more power. I haven't added any water to my 2 - 6v GC's in a year so carrying around distilled water isn't too much of a burden (for me)🙄
You're making me think :LOL:

I found one better (price wise) Bright Way 12V 110Ah AGM Battery

What aH are your 6v batteries together?
 
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