I have a garden water feature powered by a 15V Photo-Voltaic array. The PV array powers a low voltage DC pump.
Obviously, the water feature operates only when it is sunny.
It starts to run when the sun barely touches the array at a low angle (I estimate that the solar cell is at 50% of its power).
At this time, the water feature produces just enough flow to run the water through it.
At about 75% of solar power the pump gives a nice looking stream for the water feature.
In full sun the pump runs like crazy splashing water around; I had to compress the hose from the pump to reduce the flow.
As you can imagine, the annoying thing is that the fountain stops operating when the sun goes down. It is fine overnight, but even a small cloud passing over the solar battery stops the fountain.
I want to add a few 14500 Li-Ion batteries that I have left over from a different little project of mine.
I do not know how to connect them.
I am thinking of putting 3S battery pack in parallel to the pump so that the batteries are charged while the pump is operating; then when the Sun goes down, the pump will continue to run until the batteries are discharged.
Will this work, or I need some extra device to make this work?