They aren't slapping LiPos together. They aren't even using LiPos. LiPo are usually single small cells pouches in phones and gizmos. These are Li-Ion 18650 cell

They aren't slapping LiPos together. They aren't even using LiPos. LiPo are usually single small cells pouches in phones and gizmos. These are Li-Ion 18650 cells like Samsung 50e's being nickle spot welded into ~60V arrangements, with every 4.2V "p-pack" getting a wire to the Battery Management System circuit board. All charge and discharge does thru the approval of the BMS and gets cut off if any cell shows anything abnormal (short, too much resistance (voltage dipping), undervolted, overvolted). The photos look just as professionally made as another other factory. Unwrap literally any random e-bike's battery and you'll find identical construction. A few rare brands also pot the battery in thermal epoxy to make them even more safe. Yes fire and liability are scary for battery pack builders but this guys shop doesn't appear to be doing anything bad.