I've decided i'd prefer to make my own coffee and can it to have on hand when i'm in a pinch then get a bottle of cold brew at the grocery to store in the car. I wonder if anyone else has experience with this or has suggestions/oversights that could easily be made. Off hand I would think to sterilize the jar, add freshly made hot coffee which should be about 200°F directly to the jar, let it self seal. I do wonder if this going to be enough for the coffee to seal past being perishable both from quality and safety standpoint. 
For safe home canning in a water bath, you need the contents to have a pH below 4.6. Coffee typically has a pH of at least 4.8, so you need to either add an acid to bring the pH down or use a pressure canner to process the jars. Moreover, coffee is full of volatile compounds that degrade relatively quickly when exposed to air. Canned coffee would likely degrade quite a bit within a few weeks, unless you use a process more similar to how beer is bottled to prevent oxidisation. I honestly think it would be less effort to make a big pitcher of cold brew once a week and keep in the fridge for coffee related emergencies. 