I have a PCB, that is powered using a 2000mAh Li-Poly battery and Charging IC, that is powered with 5V USB cable at 0.5A. That battery last about 2 days before it needs to be charged up.
I am trying to get this charging using a solar panel. I am currently using https://www.amazon.co.uk/gp/product/B0836FKHJT/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1
I am then using a simple step down DC-DC to achieve 5V, https://www.amazon.co.uk/Youmile-Module-Supply-module-Charger/dp/B07YDFSR6D/ref=sr_1_17?dchild=1&keywords=dc+dc+step+down+usb&qid=1598093160&s=industrial&sr=1-17
This 5V is then inputted into the Li-Poly Charger IC.
This seems to be working well, when there is clouds are clear and the sun is out, but on a cloudy day there is not much charge.
Is there a better panel to use for such weather?
Is it possible that we could make a simple capacitor circuit, that accumulates the low power output from the panel, so its not wasted and can provide some charge into the charging of the battery?