Quick question, have not used my remote controller for a while. It now only charges to 75% before shutting down and seems to drain a bit faster than before. Is it time to get it changed?

Hi. Batteries are tricky. It depends how and where your battery was stored. I would start with using another charger. Then try to deplete the battery completely, literally until 0% to drain it out and try charging it again. If nothing happens, I would say that the battery is at the end of its life. For how long have you stored the battery before usage?