I have a solar garden light using a 1.5V battery charged by the Solar panel. The outer case near the solar panel is cracked. I am not sure if the solar panel still works. The light works when I use a regular 1.5V battery. The circuit board is covered with rubber putty. I scrapped off some rubber and I can see two S8050 transistors and some resistors on the board. In order to map out the circuits, I have to dig deeper into the rubber and risk breaking the working circuit. What I want is to make a LED light out of it using the circuit. I can remove the solar panel and just use a 1.5V battery. But I want it brighter (up to 4 or 5 times). I was wondering if I can just add additional LEDs (up to 4 or 5 in total). If I can, should I add the LEDs in parallel to the existing one or in series? Will the existing circuit handle the additional load?