Red Triangle, need help!

We recently purchased a 2005 Toyota Prius with roughly ~164,000 miles, which had the red triangle today. Before I go ahead with the issue, the owner who I purchased from the car had replaced the entire hybrid battery back in September, and the warranty literally expired at the end of December.

I started up the car this morning (it isn't driven much, roughly 25-30 miles a week since we bought it) the normal startup sound today was a bit louder then usual, but I didn't put much attention to it, as its been below 30 degrees here lately. After letting the car warm up, and then parking at my destination, I got the infamous red triangle, along with a check engine light, VSC, the ( (circle ! circle) ) symbol. I turned off the car, heater and radio, then let it stay off for roughly five minutes. When I turned the car back on, I noticed the engine wouldn't shut off. I decided to go ahead and go do my errands and figure it out a bit later. After roughly 30 minutes, I powered up the car, and the engine usual recharging phase was now stopping, but on the screen, it showed the battery as full (with all bars maxed out, green. It definitely which seemed to be very inaccurate. I also noticed while the engine did shut off, it would kick back on as it normally does to charge the battery, maybe after 30-45 second intervals it would do this. Otherwise, the car drove fine.

So when I got home, I ran the Techstream software and received the following error codes: P3000, P0A80, B1421, B2795. Basically, P3000 and P0A80 are my main concerns here (B1421 and B2795 keep coming back, even though key fob and AC system works fine, just an annoyance IMO). I've done some research, and am not sure what the real issue can be, as the hybrid battery was recently replaced, and the company that replaced it used a "Refurbished" battery. Some research here states that cleaning the hybrid battery fan could do the trick (I've never checked it, so could be really clogged up, but if the battery was replaced so recently, how can it clog up?). I'll give it a check anyways tomorrow morning. But in the meantime, any ideas what could be the problem? Really hoping its not a new hybrid battery, and something little...