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Comment by markvdb | Hacker News Reader

50000 kilowatt, for how many milliseconds? The phone in my pocket has a 500 _giga_watt battery. What a pity it's only 700mAh...

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No, it has not. You cannot get the energy out of that battery that quick.

That makes a huge difference. For example, TNT has about a tenth of the specific energy per kg of gasoline (4.6 MJ/ kg vs 44 MJ/kg; https://en.wikipedia.org/wiki/Energy_density), but is more useful as a bomb because you can get the energy out very quickly.

If you could get that amount of power out of a mobile phone, it would probably be a bomb.

I know you probably already realise this, but they obviously mean kWh.

I normally wouldn't comment, but to most people a kW is a kWh and, in context, it's obvious they're talking about kWh.

It's possible that they accidentally quoted the maximum power rather than the energy stored, which would make the figure correct but not what most would expect.

The linked document mentions 50,000 kW and 300,000 kWh.

Like say you get an electric car and people ask what is the range, and you answer the number for the top speed?

It's inexcusable for journalists reporting on any energy issue.

You just can't give any slack on this point. It's 100% wrong to say one thing and mean the other thing.

Not really true, I believe lithium batteries have a discharge rate limit, but still good point.

The internal resistance of a battery limits the amount of current that it can produce: https://en.wikipedia.org/wiki/Internal_resistance

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