Hot swapable battery, could it be done?

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Would it be possible to somehow wire a small 1 or 2 cell lipo (Idk how much voltage it would need) into Solo to keep the mother board, GPS and radio turned on between flights while you do a battery swap? This way, you wouldn't have to go back through the startup "waiting to hear from Solo" rigmarole and get right back to flying. There's a couple of ways this would work could work may, but probably won't work
1. Fish a small JST plug out somewhere inconspicuous and connect the battery before disconnecting the depleted one, leave it just long enough to put the SOLO battery in then disconnect it.

2. Semi-permanently wire it in and have an off switch for it when it's not needed, I think the regular battery would recharge it, or put in a USB charging port.

3. Insert better idea below

I don't guess that would really be a true "hot swap" but it's not far. Think of it like an alarm clock that runs on AC but also has a backup battery for power outages, except alarm clocks don't fly but that would be cool too. Or for my fellow shooters out there; tactical vs emergency reloads but with much less of an emergency....
 
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I would suggest a small 3S battery. You'd need to wire up in parallel with the main battery. And you'd need to have a diode on it to prevent the main battery from feeding power into the aux battery. As long as you don't go trying to power up the motors, this approach should work generally fine. When you remove the main battery, you'll lose the battery data, obviously. But when you put the new battery on, it should pick up on that and refresh all the battery telemetry and values. However, the remaining battery capacity (MAH and %) may be a little out of whack.
 
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I would suggest a small 3S battery. You'd need to wire up in parallel with the main battery. And you'd need to have a diode on it to prevent the main battery from feeding power into the aux battery. As long as you don't go trying to power up the motors, this approach should work generally fine. When you remove the main battery, you'll lose the battery data, obviously. But when you put the new battery on, it should pick up on that and refresh all the battery telemetry and values. However, the remaining battery capacity (MAH and %) may be a little out of whack.

Am I correct in understanding that as a modified option 1 in my original list? Run a T-connector, XT60 or the like out of the body somewhere to establish a temporary connection, one just long enough to make the swap?
Do you know of anyone who has done something similar?
 
Right, but you need a diode inline to prevent the 4S solo battery from pushing power into your 3S aux battery. Someone here has done something similar, but not for the same purpose. He did it to have the avionics on the small battery and the motors on the large battery.
 
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Right, but you need a diode inline to prevent the 4S solo battery from pushing power into your 3S aux battery. Someone here has done something similar, but not for the same purpose. He did it to have the avionics on the small battery and the motors on the large battery.

What if I just soldered (parallel) a 4s battery (since I already have some and I'm cheap) into the main power input but on the opposite side of the battery compartment nearest the GPS?

Battery change would go like this; Land Solo with depleted battery, connect 4s via suitably located XT60, remove depleted battery, install fresh battery, disconnect 4s from XT60, press Fly to start motors.

Theoretically, all systems should stay up, no voltage overload because it's parallel, no diode needed (I think) because nominal voltages are equal.

You're adding 2 extra steps but removing the time consuming part.

Sorry to keep hitting you with overly long and hypothetical questions, I'm somewhat new to this and am learning.
 
I guess the perfect world scenario would be to develop a dual battery pack that ran two parallel Solo batteries side by side and magically didn't get hacked up by the props or wind up being counter productive due to the added weight. Then you could just fly it like that, have double the MAH and change the batteries one at a time; replace left, then replace right or visa-versa.
 
Uh, why not an ultracapacitor? It would be fine getting charged from the main battery, and probably provide 10-15 seconds for you to swap the battery before depletion. Could be permanently soldered in place.
 
Uh, why not an ultracapacitor? It would be fine getting charged from the main battery, and probably provide 10-15 seconds for you to swap the battery before depletion. Could be permanently soldered in place.

Uh, because like I said earlier; I'm somewhat new to this and am learning.... A capacitor didn't occur to me. Sorry
 
My apologies, I wasn't trying to cast aspersions. Just wondering if I was missing something, that's all.
 
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Okay @just_bruce is this what you are thinking?Untitled.jpg
I know a little less than not-jack-crap about capacitors so could you help me out with a link to a particular one that would be able to handle the 16.8 volts and metric F**kton of amperage of the Solo battery? Please
 
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I think you need to keep the I.MX6 powered as well for a successful hot-swap.
I think everything was powered up with just the USB connected but I wasn't checking for that. I had a for parts only Solo with a lot of problems and needed a Mission Planner to resolve problems so I installed a small USB cable for easy MP connection (no UDP wireless available ). Since getting the Solo working I pulled the USB cable and can't test with the USB anymore. Maybe someone has a USB connection and can look at what is powered?
 
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The simplest method would be to connect ground power to accessory bay connector (or a current limited supercap) - swap battery - then disconnect ground power (or current limited supercap)
 
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I have one of my solos opened up on the table right now. USB powering the cube. The IMX is not getting power from the cube. And it definitely shouldn't as that would overload the cube in no time.
 
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Worth bearing in mind that a fully charged solo battery is going to have a voltage about 2-3V higher than a depleted one, so if you're using a fully charged intermediate (4S) one wired in parallel you will start charging up the depleted battery without any current limiting, until you pull the depleted one out and plug in the fresh one.. some sort of protection/limiting might be better for the battery's health and for safety...
 
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Forget about a super cap wired in parallel with the main battery.. the super cap will be depleted at the same rate as the main battery. Might be enough to keep the other stuff powered up for a few seconds during a battery swap..Maybe yes or maybe no. Someone will have to wire this up to find out for sure... but putting a small 4s battery in the AUX port before the battery swap then removing it before new flight would work every time.
Or do as I do, fly till I need a new fresh battery, land, get a nice refreshing beverage (your choice), change battery and wait till I get GPS lock, finish my drink, then fly again...
 
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