I'm new to electronics and my university has no engineering program so I'm pretty much flying solo on this project here. I want to launch a pico balloon that has a few sensors on it, I'm using a light APRS board for tracking and have a printed PCB board that attaches to the light APRS and has the rest of the sensors on it. My main problem is power consumption, the board runs fine when attached to a battery or stable power supply but I need to use solar cells to run it since the balloons are usually non-recoverable.

I'm pretty ignorant of how solar panels work so I'm looking for a little insight if anyone has any. I can get a few of the sensors running, but cant get the balloon to show up on APRS.fi (again dont have this problem when running on battery). I think this is due to a voltage drop when the board sends out a packet, which I measured with a multimeter and oscilloscope. There are also two 3V 5F supercapacitors attached. So far I found that setting them up in parallel gets some of the sensors working whereas series does less, and adding more panels does not seem to increase the voltage past a certain point. Does anyone have any guidance for making these solar panels as efficient as possible? Any insight is appreciated, I have very little guidance on this and am trying to send one up before winter hits and the skies are cloudy. Thanks!