Thanks for reading this post! I really want to get better at understanding electronics, so I want to build projects like these, but I am not 100% confident enough to just go ahead and build it. That is why I am looking for someone who would like to help me validating the idea I came up with. I made an amateuristic, but visually clear overview of my idea which can be found here.

So I want to build a solar charger capable of charging 5v devices like my Samsung galaxy s6 or other phones and powerbanks. I want to be able to charge in full sun but also when it is overcast. I like it to have a li-ion battery so it also makes use of the sun when no device is connected. It would be a nice bonus if I could also charge the battery separately with micro usb.

For the solar panels I thought using two 5V,max1A panels in parallel would be sufficient to charge in the sun and overcast. This does mean that the voltage of the panels is not always 5V because this depends on the amount of sunlight. To be able to safely charge the li-ion I thought of using TP4056 board (I will not use the microUSB but the + & - terminals). As li-ion this one should do the trick.

To make the link from the battery to the phone/powerbank I thought this board would be perfect. I think I can use it to charge my devices as well as charge the battery with protections at another moment if I wanted to via micro usb.

Now I have a few questions about this setup:

1 Would this setup work as intended and be safe to use? If not what should I do differently?

2 Is it possible to charge a phone and still let the solar panels charge the battery or is it better to implement a switch to stop the panels when charging a phone?

3 It feels like the two battery charges will be conflicting, is this true?

I would really appreciate any help on this project! Thanks in advance!

 

Better to put them in serial allowing you to have a better "sun voltage band width) power remains the same.
next step bring this down to 5V. output to phone.
then put solar power into loader ( lt1513-2 ) charge a 4.8V cell.
couple the lot with ideal diodes (mosfet + lm5050)
a: power goes via sun panel to stable 5V via ideal diode to phone.
same time cell 4.8V is loaded.
b: sun gone cell via ideal diode to phone. ( make sure that voltage keeps below 5V before entering phone)
A 4.8V cell could fully charged end up to 6-7V

good luck
Picbuster

 

Better to put them in serial allowing you to have a better "sun voltage band width) power remains the same.
next step bring this down to 5V. output to phone.
then put solar power into loader ( lt1513-2 ) charge a 4.8V cell.
couple the lot with ideal diodes (mosfet + lm5050)
a: power goes via sun panel to stable 5V via ideal diode to phone.
same time cell 4.8V is loaded.
b: sun gone cell via ideal diode to phone. ( make sure that voltage keeps below 5V before entering phone)
A 4.8V cell could fully charged end up to 6-7V

good luck
Picbuster

First of all, thanks for your help!! I see that serial configuration of the panels is indeed a much better idea! The problem only is that component supply is limited where I live and I would like to buy from the site the links in the original post are from.

I do not see the parts needed to make the ideal diode. Is it much of a problem to use a regular diode instead?

What if I only change the panels to serial and add a voltage regulator which provides 5v to the charger in the origional post. And keep the rest the same?

Thanks again for your time and effort!

 

regular diode vf ca 0.6V
Ideal diode see lm5050 could be <10mV @ n Amps e.q. SQJ860-EP
heat dissipation: function of power (current x vf ) and thermal resistance.
http://www.ti.com/lit/ds/symlink/lm5050-1.pdf this will explain all.

Picbuster

 

You don't need a diode in your set-up