HOPEFULLY 12 volt battery problem.

Today I was at the store and had a bunch of meat and frozen food and the hatch opened on my car. I loaded everything got in the car and the brake pump didn't run, then no lights on the dash, no power button light nothing. Car would lock once then would not respond. I was thinking it was the 12 volt battery and I have been meaning to replace it this year so I wouldn't run into a problem. Anyways I had someone bring a 12 volt jumper and I used that instead of another car to jump start it, nothing then after pushing the brake pedal and power switch a dozen or so time it went to ready mode, but the whole right side display was gone, and the triangle warning light was on, I drove it home. Then let it sit then it would restart just fine but still lost half of the dash displays. I got a new battery from dealer and installed it and everything seems to be fine, including the right screen. I hope I got the problem fixed. The old battery was almost 5 years old.
I also have been getting 46-47 mpg for w while now I hope that will improve, as I have read a lot of genii owners reporting worse mpg with a worn out 12volt.

 

It seems it was just the battery, Mpg did not increase with a new battery vs the failing battery.