1) 12V or 24V system? This panel is only suitable for 12V battery. If you want to use 24V battery, we strongly recommend 2 panels, connected to a serie.
2) What is the difference between policrystaline and monocrystaline panel? Monocrystaline solar cells require more complicated manufacturing process and higher energy usage than policrystaline cells, therefore the price for a policrystaline panel is lower.
3) How should I connect the panels: parallel or serial? That depends on you :) But it is very important to adapt the whole system to a chosen sort of connection.
4) Which battery type should I use? You can use any sort of battery type, but for the best functioning is the best to use solar battery.
5) Which charging controller should I use? That depends on a number of panels. Charge controller has to endure about 10% more current as the moduls can generate it in its maximum.
6) What is required when I want to connect two panels parallel? 1X MC4 plug-in, 1x Y- plug-in.