Anyone ever research smallest battery

There is a youtube video if a guy who made a super-capacitor and was able to start his car with it...not really practical unless you got a perfect tune EFI motor that starts every time in under 5 seconds and an alternator that can more than keep up with all your car demands at all RPMs

The small scooter/power wheels batteries you see at walmart with the straight spade connectors are ~12V-10Ah. A Mopar Nippondenso starter usually draws 125-250A, and is rated at 1.4Kw (1.9HP). 1.4Kw/12V =116A. The hand held "battery jumper" things you can carry out to your car when its dead usually carries 2 of these in parallel for a theoretical 230A potential. It is noted that the jump packs do say to limit the starter to 8-10 seconds with a cool down period of up to 3 minutes between cycles. The cable are usually smaller and do heat up. They have some insane jump boxes out there now. 600A out of a 18Ah battery? And all this under 1lb and fits in your glove box.....WOW!
https://www.amazon.com/dp/B01D42TYFC/?tag=joeychgo-20
BONUS>>> it has all kinds of power taps on it for USB, phone, DC jack outs, etc. pretty friggin cool.....