DIY portable handheld battery spot welder with 5 gear. for lithium battery's

PRODUCT PARAMETERS Product name: portable handheld spot welder Gear adjustment: 5 gear Battery capacity: 5000 mAH Battery type: lithium polymer battery Design current: 800A (MAX) Nickel strip thickness: 0.1 - 0.2 mm Input interface: type -C charging port Input parameters: 5V / 2.1A