Search for yourselves fellows, it is wise to do so.
In any case, as guiding beacon here's a simplified search link for AILI UPS laptop power bank on Google, videos category: https://www.google.com/search?q=AILI+UPS+laptop+power+bank&source=lnms&tbm=vid
For reference I'd choose this fellow which at least isn't using recycled laptop batteries:
It of course is better to spot weld or solder the batteries, battery contacts can cause some meaningful voltage drop at high loads and this device can drain up to 8 A from the batteries (4 A per cell).
I've been tempted to buy it sometime, but really have no need for it right now and anyway I'd prefer for it to be professionally reviewed (HKJ).
I sometimes send stuff to be reviewed to HKJ, but I'm tight on money. If someone is interested he/she can either send the device to Henrik, or make me a donation of at least ⅔ the cost for it to be shipped to Denmark. In this case (shipped to Denmark) this other seller has it slightly cheaper at ≈€12.22-12.33 total with tracked shipping: https://www.aliexpress.com/item/32990184912.html
If someone wants this to be done, I'll make Henrik confirm the item is on the way to his lab here: Review request for HKJ [USB Power Devices]