115c is way too hot.
Should be 90c and possibly 94c if idling on a hot day.
Do NOT drive until problem is corrected.
This model is sensitive to coolant pump problems.
There are other forum sites that explain how valve seats come loose at a few degrees higher.
Get the pump and its plastic housing replaced immediately.
This is also a good opportunity to replace valley hoses when it is apart.
Bob
I use a Deltran junior battery tender.
It goes thru 4 different cycles and ends at maintain.
I am quite pleased with it. It holds the battery at 12.96 volts steady all winter.
It stays on from Nov to May, and if I am not going to drive for over a week, I just plug it in and forget it.
Bob