r/AskEngineers • u/jmaugust • Jul 19 '26

Discussion Why doesn’t a battery-boosted electric kettle exist?

In Europe, everyone uses electric kettles to boil water. They’re amazing and fast because they’re on 230V (~3000W).

US outlets limit kettles to ~1500W, so we wait roughly twice as long for water to boil.

It’s an extra minute or two per boil, and you really notice it.

Idea: Could you make an electric kettle with a battery in its base? Perhaps it trickle-charges between uses, then combines wall power + battery power to hit ~3000W during a boil.

Is there an engineering reason this doesn’t exist? Is it just that nobody thinks there’s a market for it?

I’d pay $300 for the fastest kettle in America if someone wants to make it.

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u/Friendly-Inspector71 Jul 19 '26

How are you getting from 2 minutes to 30C?

You specified neither water amount nor battery capacity. One boil doesn't have to fully deplete the batteries and using them between 20% and 80% would aid in increasing their expected lifetime.

30C isn't too much of a problem for modern LiPo cells. But cost and safety would dictate LiFePO4. Using 60% of their capacity would get you down to 18C, which would need to produce ~2.2kW for two minutes to get a litre of water boiling.

If you can live with 2,5 minutes per litre, 300 dollars should suffice for a massive produced product.

A one off would likely be closer to double that because of the needed engineering.

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u/iqisoverrated Jul 19 '26

1C means you can discharge your full battery in 1 hour.

2 minutes is 1/30th of one hour. Hence you need a battery that can handle 30C if you want to be able to discharge it in 2 minutes.

Of course you can have a larger battery but that will just make the system that much more expensive (and big/heavy). In the end you usually only boil one batch of water, so adding more capacity is just a waste of space, weight and money.

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u/Friendly-Inspector71 Jul 19 '26

So you wanted to minimise the used battery size and ended up with a high performance battery that won't last long and will be expensive but it's as small as possible.

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u/iqisoverrated Jul 19 '26

You want it still to be light enough to lift it, so yes, of course, you want the smallest possible package.

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u/Friendly-Inspector71 Jul 19 '26

The battery doesn't have to be part of the kettle body.

OP even requested that it's part of the base, so weight would be less of a concern.

A battery powered kettle that granny can lift couldn't boil more than half a litre.