Building the tiniest of heaters

[Mario Divincenzo]

Im trying to figure out how to heat a small amount of water up 200 F, using a battery.
Once it reached 200, it would need to shut down. Smallest configuration possible of course. Any off-the-shelf items
i can use would be best

 

[alec_t]

How small is small?
You could perhaps use a smd transistor both for control and as a heat source.

 

[chemelec]

Sounds like heaters for Electronic Cigarettes?

 

[Mario Divincenzo]

E Cigarette heating element might work. I want to push water at 130+psi over the element to create 200 degree F water.
I would like the element and power to be no bigger than 1 1/2" cubed.

 

[jpanhalt]

Have you done any calculations. 1.5" cubed is approximately 55 mL. Raising that temperature from roughly room temperature to 93°C will require in excess of 3,850 calories (small). Now, if the water is flowing, we need to ask at what rate?

In any case, it will take a fair amount of power. What size battery were you intending to use?

John

 

[Reloadron]

E Cigarette heating element might work. I want to push water at 130+psi over the element to create 200 degree F water.
I would like the element and power to be no bigger than 1 1/2" cubed.

This isn't quite that simple. The line pressure isn't a major concern but the flow rate is. Heating water using a heating element isn't complicated but when you want instant hot then the volume of water and flow rate become key players. Forget the E Cigarette thing. Making heat with electricity takes quite a bit of power. Start with a Google of Instant Hot Water Heater and you will see descriptions like this:

Product Description

Ideal for Point-of-Use Applications Continuous Hot Water on Demand Energy Efficient Compact Design - Fits Almost Anywhere On-Unit Temperature Control LEDs Indicate Active Element and Standby Mode Standard 1/2\\\\\\\\\\\\\\\" Water Connection Rugged Brass/Copper Heat Exchanger Applications Homes Apartments Condos Hospitals Hotels Boats Restaurants Offices Laboratories ...anywhere hot water is needed! Model: RTE 9 Length: 10 Width: 7-1/4 Weight: 8 ELECTRICAL SPECIFICATIONS KW: 9 VOLTS: 240 REQ.Breaker: 40 MAX POWER(AMP): 38 AWG WIRE: 8 Minimum Activation Flow rate(GPM): 0.4 Maximum Flow Rate(GPM): 3

Take a good look at the required power. Even for a small amount of water you would need a really big battery. So we get back to how much water is a small amount and what is the flow rate of the water and the water pipe diameter?

<EDIT> John beat me. </EDIT>

Ron

 

[Mario Divincenzo]

Flow rate should be about 6ml / sec using no more than 36ml of water.

 

[dougy83]

Flow rate should be about 6ml / sec using no more than 36ml of water.

From 73F to 200F is a change of around 70K. At 6mL/sec, the power required is 4.18*70*6 = 1756W. You will have trouble doing this with a small battery.

 

[Mario Divincenzo]

I see. Thanks. It seems like an awfully heavy battery.