Hi all, I'm a bit new to electronics but I want to make a project and need your help.

I want to power a pump using a battery.
The battery need to get recharged every time the solar panel can supply the needed current but in the same time still supply the needed power to the pump.

I suppose I need some kind of a charging regulator board for this?
Also, do I connect the Solar panel in series to the battery and the pump or there are parallel connections needed?

The specifications of all parts are:
Solar panel:
20W, 5V, 1.2A (All rated for max output, after the regulator)
Pump:
3.5-9V, 1-3W

how would you make this? and what battery would you use?

 

So the solar panel outputs 5V when delivering max power , that's about 7 V open circuit (No load) ...

You would not need a very big battery , and no regulator is needed if you have a battery protection circuit ...

The voltages for the panel and the pump don't match very well ... lithium is the best choice for battery and you may get away with 1 cell .... that's a voltage between about 4.2 and 3.6 ... the pump will be a bit under powered , but will work ...

You just need two components ... the battery ...

just one of these is enough ... get a recognised brand panasonic ..6 pounds UK it will hold 10WHrs enough to run the pump 10 hrs (at 4V) https://www.ebay.co.uk/itm/3400mAh-...hash=item3b30608f3d:m:mW6lttqfQ7vbdhaCtnaVZCg

and a protection circuit ..... many different types .... very cheap

this will connect panel with battery and prevent overcharging , and the pump is connected to the battery

https://www.ebay.co.uk/itm/1S-5A-3-...985889?hash=item23b0dad1a1:g:4sIAAOSwvmNbKJ21

 

Thanks for the quick reply!
I'll order the parts and get back with the results

 

Thanks for the quick reply!
I'll order the parts and get back with the results

It might be better to by the 18650 cell with tabs (search eBay "18650 tabs"), it will make it easier to connect , without tabs you may need a cell holder