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Compact grey ABS spot welder with dual copper pens and small digital display

BFKK

BFKK 5000W Battery Spot Welder 18650 0.1-0.25mm

SKU CH-02PK-34XNS

Portable 5000W spot welder with adjustable current welds 18650 lithium batteries using 0.1-0.25mm nickel sheets and includes a digital voltage display

  • 5000W output power handles 18650 battery pack welding
  • Adjustable current suits 0.1-0.25mm nickel sheet thickness
  • Built-in 4000mAh lithium battery enables portable operation
  • 28-inch digital display shows remaining battery voltage
  • Foot-switch trigger completes welds in about 0.5 seconds

Portable 18650 battery spot welder

This 5000W spot welder is built for assembling 18650 lithium battery packs with nickel sheets from 0.1mm to 0.25mm thick. It runs on an internal 4000mAh 60C lithium battery and includes a 0.28-inch digital tube that shows remaining voltage. The ABS shell houses pure-copper welding pens with replaceable tips. Operation is handled by a foot switch and a current-adjustment knob.

Upgrade from fixed-output or mains-only units

Unlike basic welders that offer a single power level or require a wall socket, this model lets you dial the output current for 0.1-0.15mm nickel-plated steel or 0.1mm pure nickel. The jump is worth it when you need portable pack building without hunting for AC power, and when replaceable pen tips cut consumable cost over sealed-head designs.

Sustained use on battery power

The 4000mAh pack delivers repeated 0.5-second weld pulses while the digital tube tracks voltage down to the 7.3V recharge threshold. Working temperature spans 10°C to 65°C, so output stays consistent in a warm workshop. Low standby draw preserves charge between jobs, and the unit must not be used while charging to protect the cells.

Highlights

  • 5000W output power handles 18650 battery pack welding
  • Adjustable current suits 0.1-0.25mm nickel sheet thickness
  • Built-in 4000mAh lithium battery enables portable operation
  • 28-inch digital display shows remaining battery voltage
  • Foot-switch trigger completes welds in about 0.5 seconds

Specifications

No published specifications for this item yet.

Questions about this item

What are the body dimensions of the BFKK 5000W spot welder?

The body measures 6.5 by 3.86 by 2.36 inches and uses an ABS shell for a compact, portable design.

How do you perform a weld with the foot switch?

Place both copper pens on the nickel sheet, press and hold the foot switch until the red light flashes three times and the welder outputs current once, then release the switch.

When should the built-in battery be recharged?

Recharge when the digital display shows the voltage dropping below 7.3 V; the 4000 mAh lithium pack charges at 8.4 V and 500 mA.

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