I'm trying to develop a portable 'Thermos' style flask that heats around 500ml of water within 1 hour for on-the-go use.
Thanks for all your answers - much appreciated.
I need it to heat 500ml of water to around 80C (enough for a hot beverage) so that the user can then add instant coffee/tea. I've looked into the technology behind zippo handwarmers using lighter fuel and a catalytic converter. I must either have a working model or perhaps just a prototype with a separate model simulating the technology within the flask.
I need it to be fairly innovative so using batteries wouldn't work for this (plus it would be too bulky).