1.5 year old Steam Deck 2 minute battery life

I've had my Steam Deck for about a year and a half. Battery life has never been great, because it's a Steam Deck, but I found recently, I can unplug the charger and watch the battery drain. It went from full charge to shutting down, I timed it at 2 minutes and 10 seconds. That's not even running any games, just in the desktop. Similarly, I plug in the cord and it charges back to 100% within a few minutes.

I generally only play plugged in, but it might be nice to be able to move to a different room in my house without needing to run. I charge with the cord that came with the Steam Deck and a 45w charger.

Is there anything I can do to reset the battery? Is it with the cost of replacing the battery?