SUNKKO 737G+ Battery Spot Welder (4.3kW Dual-Pulse) – Professional Handheld & Fixed Spot Welding Machine for 18650 / 21700 Lithium Battery Packs

Overview 

The SUNKKO 737G+ is an upgraded, high-power 4.3kW dual-pulse resistance spot welder engineered for assembling, repairing, and manufacturing 18650, 21700, and 32650 lithium-ion battery packs. Designed for high efficiency, the 737G+ offers both a fixed inductive welding head for high-speed single-cell assembly and a S-70BN ergonomic mobile welding pen for constructing large-capacity battery banks, e-bike battery arrays, and solar storage packs. Featuring precise digital current regulation and multiple pulse selection modes, it produces clean, ultra-strong spot welds on nickel plated and pure nickel strips without causing thermal damage to delicate battery terminals.

Key Features 

• Dual Welding Modes: Micro-controlled fixed welding head for benchtop production alongside an external 70BN mobile welding pen for large, heavy-duty battery packs.

• 4.3kW High Peak Power Output: Delivers instantaneous high-current pulses capable of penetrating 0.05mm to 0.35mm pure nickel and nickel-plated steel strips.

• Smart LCD Parameter Display: Real-time digital readout of pulse number (1–18P), current level (0–99), and pulse sequence settings for consistent weld quality.

• Inductive Automatic Welding: Fixed head features automatic press-down contact sensing—welds instantly upon contact without requiring a foot pedal.

• Adjustable Needle Pressure: Top knob control allows precise adjustment of welding pin contact pressure to eliminate sparking and material burn-through.

Technical Specifications 

Common Applications 

• Custom lithium-ion battery pack manufacturing (18650, 21700, 26650, 32650 cells)

• Electric bike (E-bike), electric scooter, and EV battery bank assembly

• Solar power storage system (LiFePO4 / Li-ion) array rebuilding

• Power tool battery pack repair (DeWalt, Makita, Bosch, Milwaukee packs)