Solar Pathlight -have they been improved?

I purchased the smart lighting bundle from Costco about 2 years ago. It came with 4 solar pathlights. I am now down to 2 lights and the solar panels no longer charge. I’ve been bringing them inside to charge via USB. Two lights are totally dead (I’ve attempted multiple things to verify they are dead.) and before I buy anymore I want to know if the device has been improved from the gen1 product I have? They are expensive for a path light and I don’t want to spend $35 ea if they don’t last much past the warranty period. Feedback is requested. Thank you!