My first build - Planning stage - need guidance


New member
Aug 1, 2020
Good day,

So far, I have learned a lot from this forum, so thank you!

I am ready to begin my first build. But I need some guidance on a few things (well a lot I am a noob).
USE: A battery pack for use in backcountry camping/paddling to charge electronics (mostly via 5v USB) and charge via solar power

Current set up
I currently use a mash-up of off the shelf battery banks and a small solar panel.
Goal Zero Venture 30 7800mAh (at 3.7v)
Blackweb 6600 mAh
Pny 7800 mAh
Anker Power Core 20100 mAh
Black Web 20100 mAh
Goal Zero Nomad 7 solar panel - 7W - 8-9 Voc (but has a 12v out)
Goal Zero Guide 10 battery charger


I keep all of this is a Pelican 1300 case. This is fine for a week or two out in the backcountry, but I want better power density and fewer loose components. Also, some of the cheaper battery banks (Small blackweb) do not charge very well from the panel.

I charge various small devices like, headlamps, GPS, Satellite communicators, Cameras, and the occasional phone. Everything uses 5V USB connectors to charge or AA/AAA batteries.

Id like to keep the battery and connectors inside the Case.
Case to remain watertight when closed. Although I would like to charge from solar with it closed.
4 to 8 USB ports (2.1A)
Battery charge indicator
Solar Connector x 2 (I plan on upgrading solar panels as my current one is probably underpowered)
Ability to charge from AC (Wall wart)
Enough room in case to store cables.
Have more stored power than the current set up (more than 62400 mAh)

I currently have the tools and supplies for Anderson Powerpole 15/45 connectors
I can solder
I have a 3D printer and can design in fusion
I am not afraid of blowing things up if I learn from it.
I do have another Solar Panel 25W 18Voc
I plan on eventually getting a foldable 50W or 100W Panel

Questions I have
1. What should my pack voltage be when I configure my cells? I have no plans to ever add an AC inverter and again my devices all charge from 5V USB. My thought is 12V (14.4V) for charging from the solar panels and step down to 5V for USB
2. What BMS and solar charger would be good options for this? Not looking for the cheapest, but cannot break the bank either
3. Does anyone have any other builds like this or any suggestions to add to this?
Thanks in advance!



Jun 28, 2020
My recommendation is to get/build a bank/pack that outputs between 22-28V DC then connect that to the very efficient tiny 100WDC to QC/PD buck converters mentioned here. This will give you almostevery USB output voltage / protocolin use, up to PD 20V/5A, and you can also use the trigger shown thereto convert it into DC barrel output, which essentially yields a universal 100W powerbank.