Portable Power Supply

[XERTYX]

Well I've finally done it. I want to first build a portable solar bank before I build a stationary one. 

The last bank I built didnt even have a charge controller as I couldnt afford it. I sourced the panels from Hong Kong and paid pennies on the dollar but couldnt find a charge controller I could bidsnipe. 

There have been a lot of improvements since then and there are so many choices. But I never follow the norm. I like to take a simple problem and make it more difficult.

So what I have done is to assemble the following components. 

•25w Dual USB output flexible solar panel (I couldnt find a 30W on the cheap)
•2 20Ah 74wh Lithium USB banks with dual inputs
•USB buck converter
•12v 5 watt LED Light Bulb
•Cabling Switches misc

I havent had a chance until today to test the panel in full sun and it was cloudy until 1230ish but I have found one thing that seems to ring true so far. 

It works much much better if you plug one of the USB solar outputs into each bank AND connect the 2 together using USB-C to USB-C if one of the banks has 00% remaining the panel alone doesnt seem to accept a trickle charge under cloudy conditions but the usb-c charge keeps it awake and it charges more quickly. The second bank just fills to 100% and the excess goes into the dead battery.

The 12v light bulb seems to draw around 6.1 watts according to the buck converter. But in practical usage the bulb will only burn for around 9 hours 45 mins which leads me to believe I've gotten a 7 watt bulb and the bank will only discharge to around 75ish +/- depth of discharge rather than 80% DOD

I'll try and post pics soon and update my progress.

 

[lenny flank]

So what was the total cost, compared to a similar premanufactured version?

 

[XERTYX]

Umm I'll look into that I'll even post links to the exact equipment I went with. I did buy everything with prime shipping. It could be done cheaper if shipping time wasnt a concern.

Off the top of my head I'd say around $120 and unlike a jackery or similar the usb banks are far smaller.

 

[SheketEchad]

I, too, am considering just a portable unit. My initial purchase will probably be a hi-top conversion van and I don't want to install panels on it in case I decide to change vehicles, or want to go tent camping with it, or camp in my car as opposed to the van.

This is what I am considering:

2x 500 Watt Kyng UPS back up solar 'generators' 567.00 ( Battery 500w Continuous 1000w Peak -288Wh/500W, also has Pure Sine Wave inverter)

1 Intergy Apex Gold system 2290.00 (Generator Cell Type: Lithium-Ion (NMC) Battery. - Peak Capacity: 1,100 W continuous for 1 hour, 3,000 W peak.- 12.6V DC, 90 AH.- Up to 2,000 charge cycles. Pure Sine Wave AC Inverter with a 1,500 Watts Continuous, and 3,000 Watts Starting Surge Output, 500 watts of solar panels, MMPT charge controller, all cables, connectors and some 'free' lights.

The reason I chose this particular package is for the RV plug in option, or in case I ever get one of Jim's recommended handy dandy 410 watt a/c units and the fact that it charges in three hours in optimal conditions. Almost any day here in the SE will give you three hours of sun unless it's a hurricane week. Then I will either be out of the hurricane path or in my S&B hunkered down

I already own 1 100 Watt Panel and 1 60 Watt panel (150.00)
Also own a Jackery 240 (249), Powermate 500 W and Powermate 400 W (B&D things only rechargeable on 120V)

The B&D powermates are at least 6 years old, so we won't count their cost. The rest comes out to 3,256.00

If I lived close to AZ, I'd go get Santan panels, but I think the voltage output would be too high for my portable 'battery banks' except maybe the Apex, since it has the charge controller. Their used panel prices look freakin' awesome. But the cost of gas to get there or shipping to me outweighs what I can get here (maybe, unless I bought some kind of bundle thing from them)

I think it will cost close to the price of my van, but I need to ensure that I have enough power to work my job even on cloudy days and I don't want to install it ON the vehicle. I will go with the rigid panels, even though I'd like the half weight of the Linx panels as far as tote weight, due to the high cost difference between flexible and rigid panels.

It is expensive. I don't like that part. I'd rather buy in piecemeal if I could rather than bellying up all at once. If I did not have to work I wouldn't worry about power needs and stick with two of the Kyng power units and two 100 Watt panels and the Jackery. However, it is close to the cost of two year's power costs at my S&B, which after a year I won't be paying. So 4 years to pay for itself. Not a bad ROI. I'm sure if I were mounting on the vehicle, I could do it for less - how much less I don't know. I think there is a hefty surcharge for people who don't want to mess with wiring, fuses, what gauge of wire, and whatnot.

But I've not bitten the bullet yet, just considering it (since I don't even yet own the vehicle, lol)

 

[XERTYX]

After considering the days solar recharge even though one of them was 0% I realize i need a dedicated charger for the portable pack and the portable panel is just a backup charging method while I'm in the field.

The panel came in a kit with a 10A pwm controller and cabling to use with the controller if not using USB. So i had already thought of buying a small AGM battery to use with it with the 4 5 watt panels i have from the old days.

I'm thinking of getting a 100 watt poly panel off of amazon and a 29DC walmart deep cycle for the vehicle. Then I can use the QC 3.0 12v to USB socket i also bought to charge the portable unit in the car and have enough juice hopefully to add an alpicool c20 to the vehicle in the future.

In the mean time I'd focus on all of my power needs coming from the USB banks and daily recharging. That way I wouldnt rely as much on the house battery.

I had thought of trying to run a DC fridge when I get one on the usb buck converter but I've discovered that it doesnt matter much how many amps you're pulling from the bank the port will not supply more than 15 watts.

The buck converter has up to 2 amps output so 12v X 2A =24w but the port will only supply 15 watts max. If I really wanted to Dr Frankenstein it I suppose I could use 2 buck converters from different ports and combine them using diodes and have 30W supply. I could also try and run 3 converters joined for 45W I have thought. Maybe then I could run a hotlogic mini. I know they're rated at 48w but idk if they peak out.

Anyway just my 2 cents and observations using $18 phone chargers.