Thank you! I enjoyed reading your reply and wanted to make some comments on it.
It was one heck of an undertaking to complete on my own in my spare time -- especially since my discipline in Mechanical and Electrical engineering is all self-taught; I'm a software engineer! I worry that if this were ever to be mass produced the quality would go down and the "NO COMPROMISES" mantra I had while creating this would be thrown out the window. That is why I made this for myself and possibly will sell the one extra I've provisioned for -- if I can find the right buyer. That being said, for the one-off version I'd build the $500 you mentioned wouldn't even cover the cost of the power supply module and Pelican case -- so unfortunately that number is *WAY* off.
As for the patent aspect, I've gone down that route before both as an employee working for a company and an individual and believe me there is no point in spending the money it takes to get a patent for this, and then even MORE money defending that patent should someone breech it.
The case weighs 42 lbs fully loaded, and the top of that Pelican case is going no where with wind, knocking into it, or any other accidental gesture to close it. While the XT60 wires do stick up when in-use, it really does not post an issue with the lid coming down on them. The AC Line cord / DC input cable will also provide resistance for the lid preventing it from coming down too hard on those connectors (and the only way it comes down is if someone forces it down on-purpose). Nevertheless, your idea is a good one and I welcome more feedback like that -- especially from someone who is a real industrial designer!
The hardest part (and one that I had very little outside control over) was getting the G10 material and aluminum anchors machined. Since this was such an undertaking to have done I had TWO sets made -- initially as backup and then later on in case I decided to sell the extra set in a completed second unit. I still have to add up my total bill of materials, but again I purchased the parts at retail without the plan to source OEM components for mass production. For me to buy all the parts again, take the time to custom assemble another one, etc it would be pretty costly. I need to find the right buyer (A professional who gets paid for professional work; and pays for professional work in return) in order to build out the second unit.
As Mad_angler1 had posted, that is exactly correct -- the balancing is all done in the battery itself. The charge hub simply looks at the voltage of whatever batteries are connected and distributes power to the two highest voltage packs (the 2 closest to being fully charged). There is no intelligence in the power supply, charge hub, etc. It is all done in the batteries.
I too have experienced this. DJI is pretty stingy with the rules they enforce when it comes to their batteries and what they consider "safe" and "flyable" -- but as a manufacturer mass producing aircraft like this they have to be. I've had the same problem with 2 of my older batteries (always charged on OEM charge hubs and power supplies). It's just their algorithms and tech inside the battery that causes this, it's unrelated to the charge hub or power source.
That thing is a joke compared to what I have built. If it works for you, that is great -- but where that does 2.5 amps (per battery? total??) mine does up to 10 amps per battery, 60 amps total output. Mine also has the ability to run from many different power sources and can charge batteries very quickly in the field -- that was the purpose of my creating it.
