Flask and cooling pack-hybrid?

Pawnless Endgame · 12 Dec 2015 at 19:17

I normally carry a 1L vacuum flask with ice and water to keep it cool. When there's not much water left, the ice rattles inside!

I've tried a cool box too with cooling packs. Although still fairly small (lunchbox-sized), it doesn't allow me to fit much else in my backpack.

So is there a such thing as a flask with coolant inside the walls (where the vacuum normally is), that you can lob in the freezer overnight?

Thanks in advance.

norm · 12 Dec 2015 at 19:46

That's a pretty good idea. Might want to check patent records quick. : )

Rich1988 · 12 Dec 2015 at 20:32

isnt that vacuum what makes it good at actually keeping the heat in/out. so stick liquid in there and it loses all thermal properties? perhaps a seperate area with coolant jacket inside? or outside?

adolf hamster · 12 Dec 2015 at 20:50

Why do you need your water so cold this time of year?

Pawnless Endgame · 12 Dec 2015 at 21:03

Moses said:
Gel cool pack inside?

Cheers, will have a nose for that.

adolf hamster said:
Why do you need your water so cold this time of year?

Runs in the family. My granny is 86, still sleeps all year round in a 4.5-tog with a window open.

And what Elsa said - "The cold never bothered me anyway"

My sister is the exception in my family though... central heating on in July :rolleyes:

Muban · 12 Dec 2015 at 21:10

I saw Chillys bottles on Amazon and was going to get one to try them out. Not got one yet but the reviews seem pretty good. Their own site claims they keep cold drinks cool for 24 hrs.

Pawnless Endgame · 12 Dec 2015 at 21:27

Thanks Muban!

My parents have been nagging me to update my Amazon wishlist, so I have added the blue version (750ml) on there :-)

Craig321 · 12 Dec 2015 at 21:41

Coolant stuff inside would still be a good idea though, surely that'll work better than any flask, especially if you combine it with whatever design those Chillys ones have.

Dis86 · 12 Dec 2015 at 22:02

Craig321 said:
Coolant stuff inside would still be a good idea though, surely that'll work better than any flask, especially if you combine it with whatever design those Chillys ones have.

It's a terrible idea. What makes coolants good at cooling is the ability to rapidly absorb and desorb thermal energy.

You'd find your drink quickly assuming ambient temperature.

itchy · 12 Dec 2015 at 22:35

What coolant are we talking about, as far as I know the is no coolant on the planet the cools on its own.

Flasks have a vacuum to keep the outside temperatures out and inside in.
The only way you could produce a coolant without mechanical or refrigeration, would be a one way chemical reaction by rapid expansion of gas. Once used it would become useless.

Pawnless Endgame · 12 Dec 2015 at 23:27

Sorry, I meant coolant as in the liquid found inside ice packs.