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Please go gentle as I am a novice at electronics/battery issues.

I am hoping someone with a much bigger brain than me can answer this question...

Is it realistically possible to power a 1200W hotplate with a battery and if so what sort of spec battery would I need?

I am looking to power something like this...

enter image description here

(Product link)

My research shows me that an average kitchen hob uses around 0.72 kWh per use. I'd imagine something like a portable hotplate would use less but this is a good measuring stick.

I truly appreciate anyone giving this any thought.

Thanks.

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    \$\begingroup\$ If the answer involves the use of several car batteries, would you still be interested? \$\endgroup\$ – Andrew Morton Nov 12 '18 at 19:01
  • \$\begingroup\$ The high-tech, lithium-polymer battery in my plug-in hybrid car supposedly stores enough energy to run your hot-plate for about six and a half hours. It weighs four hundred and fifty pounds (a bit more than 200 kg) \$\endgroup\$ – Solomon Slow Nov 12 '18 at 19:11
  • \$\begingroup\$ Thanks for your replies. Several car batteries wouldn't be ideal 😂 but if that's the only way I can do it at least I can write it off. \$\endgroup\$ – nickjchelm Nov 12 '18 at 19:51
  • \$\begingroup\$ Solomon re your car, all joking aside with some basic maths that can at least provide some helpful information (although I'm sure it's not as simple as that!). I'll need to power the plate for about half an hour so about 15kg worth of battery could work. I was thinking/hoping that ballpark figure. Anyone with any ideas where I could find one? \$\endgroup\$ – nickjchelm Nov 12 '18 at 19:54
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    \$\begingroup\$ @nickjchelm - this isn't a forum. To add additional info you need to 'edit' your original question. But using 'stored electricity' to create heat is rarely an efficient use of the 'stored electricity' or the space used to store it. You'd get much better energy density by storing a liquid fuel (or liquified compressed gas) and burning it. \$\endgroup\$ – brhans Nov 12 '18 at 21:06
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tl;dr: Possible? Yes. Practical? No.

Some quick back of the envelope math... First of all, your stated 0.72kWh average, on a stove with a 1200W (1.2kW) power draw, means you're only getting 36 minutes of runtime before you need to recharge (0.72kWh/1.2kW = 0.6h). But sometimes you may want to cook something that takes a little longer, so let's be more generous and plan for 1 hour of cooking, or 1.2kW of storage.

Suppose you use lithium-ion batteries. A common lithium ion cell has a nominal voltage of 3.6V, and usually somewhere around 3000mAh of storage, for approximately $5. That works out to approximately 10-12W of energy storage per cell. Here's one example: https://www.18650batterystore.com/Panasonic-18650-p/panasonic-ncr18650b.htm .

If we were to construct a battery using these cells, we would need over 100 of them, which would be fairly bulky, and already we have $500 in cost not including the connections and electronics to make it all work.

If instead we used a cheaper battery chemistry, such as lead acid, it would greatly increase the size and weight, and it would be a stretch to call such a device "portable". Here is a single-battery solution that would provide the needed 1200W, but it costs $290 and weighs 65lbs (30kg): https://www.batteriesplus.com/battery/sla-sealed-lead-acid/12/wkdc12=100p

And $300-500 could buy quite a lot of kerosene or propane for a more conventional portable stove, which would provide much more than an hour of runtime.

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    \$\begingroup\$ @nickjchelm: Nate's deep-cycle lead-acid battery may manage to cook one meal - but how do you propose to recharge it for the next meal? A propane or kerosene stove would be much more practical for an extended camping trip. \$\endgroup\$ – Peter Bennett Nov 22 '18 at 1:50

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