Repairing Aldi solar christmas lights

Specifically the colour version of these "Casalife" solar powered christmas lights (I'm assuming they're all the same inside).

For $9.99 in the middle isle who wouldn't be tempted? I've been fiddling with assorted solar projects so thought even if they broke instantly I'll at least get maybe a battery cell & a dinky panel out of it!

They lasted about 2 days before they'd randomly start flickering on and off quickly and strobing our neighbors! It took me a while to finally get around to taking them down after turning them off (laziness etc.). But once they were down I opened them up and was surprised to see the solder connection for the LEDs to the control board was broken! Re-soldering this joint fixed the lights entirely.

Inside was a simple board with pads for the battery pack (1800mAh), the solar panel, & pins for the basic LED strip. I don't own a working multimeter right now so I didn't look too deep into everything. Thats a project for next time!

Ideally I'd like to put an ESP-32 inside here and have them be "smart" lights, but I lack the connectors to do it safely without soldering everything directly to the board. Might tackle this another day.