What would be a better medium for "cooler cells"? Answered
Talking about making cold packs by reusing plastic bottles. They'd be used in a portable cooler (stacked between spacers for airflow).
The obvious option would be just water, but I was thinking something a bit more creative.
~water and salt
~water and alcohol
~water and antifreeze
(The bottles would likely need to be epoxied shut to prevent leaking. Their life would also matter, can't have stuff growing in them after a few uses.)
Which do you think would stay cooler the longest?