68800mAh Power Bank+Jump Starter, really ? - or what's in it - a tear down and capacity test

Another brilliant piece of Chinese engineering, fairly well made, but apparently someone must have got the maths seriously wrong.
We took a look inside and it's actually not too bad, but the first capacity test was rather disappointing.
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The sticker states 68800mAh (at an undisclosed voltage) that's 68.8Ah, and assuming a nominal voltage of a 3S LiPo setup at 11.1V this would be around 760Wh, or 0.76kWh.
Our very first brief capacity test revealed a disappointing 22Wh (0.022kWh), or 2Ah (2000mAh) that's about 3% of the stated capacity.
The battery inside looked like something in that region, so not much of a surprise.
We will do another video starting from a confirmed fully charged battery, discharging with constant current and some data logging to document the full cycle. It is not expected that the results are much different because it took less than 4 hours to get it re-charged, at a maximum of 12V/1A minus charging efficiency, we got an idea how much energy is now in it. ...25Wh is probably a good guess.
It was not expected to get anywhere near the stated capacity, but 3% is a rip-off, even we may end up with 4% in the second test, the value for money is pretty poor.
Since i took it apart i cannot return it, but the seller will certainly get an angry email because this is misleading advertising (purchased in the UK, not in China)
Maybe someone has an idea how the secret Chinese maths make 68AH of this, because good old Ohm's Law i've learned many decades ago does not provide a solution to reproduce their numbers.
This units come with various brand names but look pretty much all the same, just different stickers on it.

My conclusion:
Not fit for purpose !
A starter motor (even on a small car) draws around 100 to 150A, when engine is cold.
Assuming this thing has no more than 2.5Ah, this would be 40 to 60C for at least 5 to 10 seconds, probably longer, which most likely kills the cells straight away. At least i would like to be as far as possible away from it as it's not exactly fun to be near an exploding LiPo pack....don't forget your safety gear when you try it !

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