Battery Powered heating element

Discussion in 'Power Electronics' started by flare09, Aug 22, 2016.

  1. flare09

    Thread Starter Active Member

    May 17, 2012
    So I'm putting together a little project that i would like to power by battery.

    The main power draw is a stainless steel heating element wrapped in kapton. Much like this here,

    I wanted to use this board to power the element. But im not sure if this is the correct way to go about it. (if link is broken, it is the powerboost 1000 unit by adafruit)

    Splicing the positive and negative into a usb cord to connect the heater to the board.

    I am aware i will only push 5.1V into the heater. And Since the heater is a resistive load, resistance increases with temperature, do you think that board will fry (minus the fact it has thermal shutdown) itself out trying to power the heater? I would prefer this route because i could switch out the heater to charge a phone, and still utilize the heater while the battery is charging.

    For shitznsafetygiggles i was going to also add a normally open auto reseting thermal cutoff switch, between battery and board. With the sensor on the heating element, that way it doesnt run away and it only get s up to a max temperature i choose
  2. Alec_t

    AAC Fanatic!

    Sep 17, 2013
    What battery do you envisage using? The heater draws 0.75A at 5V, so if you used a 3V (for example) battery to run the booster the battery would need to supply 0.75 x 5/3 = 1.25A (assuming the booster is 100% efficient, which it won't be).
    Last edited: Aug 22, 2016
  3. flare09

    Thread Starter Active Member

    May 17, 2012
    I would like the device to last at least a constant 2 hours. But it may be less. A protected 18650 should be the most logical option, based on availability, and most common discharge peek being 10A or more.