AWithZ UF20B supercapacitor spot welder: small size, big power

Wanwu Wulian unboxes the UF20B supercapacitor spot welder: aluminum-alloy case, 1750A/10.5kW, rated for 0.15 copper / 0.4 nickel; accessories are sandpaper, nickel strip, welding pens (with manual switch), power cord; two front buttons, foot-pedal port, dual pen ports; manual gear 10 welds 0.12 + 0.24 nickel strip so tight it needs pliers to tear apart; gear 52 welds a 0.38 utility-knife blade to 0.24 nickel strip solidly; 99 gears; comments: ¥570 is too much, sticking with a relay / ¥600 hand-builds a 4-capacitor rig

Opening: a 0.38 thick blade and 0.24 thick nickel strip spot-welded together, at only half power. Introducing the AWithZ supercapacitor spot welder: main unit + accessory box (a sheet of sandpaper, a pack of nickel strip, a pair of welding pens, a power cord); refined aluminum-alloy case, model UF20B, max output current 1750A, max power 10.5kW, rated to weld 0.15 thick copper strip and 0.4 thick nickel strip; two buttons on the front, one foot-pedal port, two welding-pen ports; the welding pen has a manual switch, so you line up first and then fire, more convenient. Power on with a long press: you can set weld mode, preheat time, interval time, gear, trigger time, pulse count (screen shows 20ms, T 31°C). Plug in the pens, manual, gear 10, welding on a Li-ion cell: 0.12 and 0.24 nickel strip, bright welds with no blackening, can’t be pulled off by hand, pliers needed, both strips shred before they come off. Then a 0.38 utility-knife blade + 0.24 nickel strip, gear set to 52, judging by the sparks the power is serious, and even this thick it welds solidly, only comes off once the pliers tear it apart; a professional spot welder indeed, 99 adjustable gears cover most needs. Comments: ¥570 is too much, sticking with a relay (3); for ¥600 you can hand-build a 4-capacitor rig, though the compact looks are nice; five hundred-something; do a teardown; DIY is better; under two hundred would be fine.

Outcome

Steps5 steps · click a frame to jump

1. 
   1. Opening: 0.38 blade + 0.24 nickel strip, welded at half power

   The power is fierce — a 0.38 thick blade and 0.24 nickel strip spot-welded together, at only half power.

   00:00 – 00:13
2. 
   2. Accessories and unit: aluminum case, UF20B nameplate 1750A/10.5kW, welds 0.15 copper / 0.4 nickel

   Accessory box: sandpaper, nickel strip, a pair of welding pens, power cord; refined aluminum-alloy case; UF20B 1750A, 10.5kW; rated for 0.15 copper strip, 0.4 nickel strip.

   00:13 – 00:38
3. 
   3. Two front buttons, foot-pedal port, dual pen ports; pen manual switch; menu items

   Two buttons, foot-pedal port, two welding-pen ports; the pen has a manual switch so you line up first then fire; after power-on you can set weld mode, preheat, interval, gear, trigger time, pulse count.

   00:38 – 00:56
4. 
   4. Manual gear 10 on 0.12 + 0.24 nickel strip: bright, no blackening, only comes off shredded

   Plug in the pens, manual, gear 10; weld 0.12 and 0.24 nickel strip on a Li-ion cell; bright welds with no blackening; can’t pull it off by hand, pliers needed, both strips shred before they come off.

   00:56 – 01:12
5. 
   5. Gear 52 welds a 0.38 utility-knife blade + 0.24 nickel strip solidly; 99 gears

   Gear 52; the sparks show serious power; solid even this thick, only comes off once the pliers tear it apart; professional; 99 adjustable gears; check it out if interested.

   01:12 – 01:31

Bill of materials

Creator’s tips

• Pen manual switch: line up first, then trigger 00:38
• Thin nickel strip is bright and solid at gear 10; thick material at gear 52 00:52

Pitfalls

• Comment: the ¥570 price is a barrier; the DIY crowd reckons ¥600 hand-builds a 4-capacitor rig

Li-ion safety

Quotes

Cost & time