Pulse Spot Welder 801D

801D Capacitor Energy Storage Pulse Spot Welder — for 18650, 21700 & Battery Pack Building

The 801D is a dedicated battery spot welder built specifically for welding nickel strip onto 18650, 21700, 14500, and LiFePO4 cylindrical cells. It uses capacitor energy-storage pulse technology to deliver a precise, high-current weld in milliseconds — clean results, no blackening, no circuit tripping, and no damage to the cell underneath. This is a best-selling model and the go-to choice for DIY battery builders, e-bike pack assemblers, solar storage builders, and battery repair shops.

Why the 801D?

• 14.5 KW peak pulse power from dual super-capacitor core — fires in milliseconds with zero grid interference
• Welds pure nickel strip 0.05–0.3 mm and nickel-plated strip up to 0.4 mm directly onto 18650 cells
• Also welds aluminum-nickel composite sheet onto LiFePO4 prismatic aluminum electrodes (0.05–0.15 mm)
• 2 welding modes: AT (automatic trigger, hands-free for high-volume pack building) and MT (foot pedal, for precision and parameter tuning)
• 99-level energy adjustment — dial in the exact output for each strip thickness and cell type
• LED display shows welding power, capacitor voltage, and live instantaneous current during each weld
• Compatible with both 73B mobile welding pen and 73SA push-down welding arm — both included
• Aluminum alloy housing for heat dissipation — rated for up to 12 hours of continuous use without overheating
• Universal 100–240 V input — works on standard U.S. outlets, no step-down transformer needed
• Compact and lightweight — smaller and lighter than traditional AC transformer welders, easy to take to the job site

Ideal For

• DIY 18650 / 21700 battery pack building for solar storage, e-bikes, power tools, and electric vehicles
• LiFePO4 battery module assembly with nickel-aluminum composite strip
• Battery repair and rebuilding shops doing volume welding with AT mode
• Schools, makerspaces, and labs teaching battery pack assembly
• Any application requiring clean, consistent nickel strip welds on cylindrical lithium cells

Technical Specifications

What's in the Box

• 1× 801D Spot Welding Machine
• 1× 73B Mobile Welding Pen
• 1× 73SA Push-Down Welding Arm
• 1× Foot Pedal Switch
• 1× Power Adapter (15 V)
• 1× Power Cord (US plug)
• Spare Welding Pins (for 73B pen)
• Spare Welding Needles (for 73SA arm)
• 1× Hex Key Set
• 1× User Manual

Full Description

Welding nickel strip onto lithium cells is a precision task — too little energy and you get a cold weld that pulls off under vibration; too much and you damage the cell's internal structure or burn through the strip. The 801D solves this with capacitor energy-storage pulse technology: it charges two super-capacitors gradually from a standard wall outlet, then releases that energy in a single millisecond burst. The result is a weld that is metallurgically sound, cosmetically clean, and cell-safe every time.

Unlike traditional AC transformer welders that draw surge current directly from the line — causing breaker trips and inconsistent welds under varying grid conditions — the 801D is fully decoupled from the grid at the moment of the weld. You can run it in a garage, a van, a storage room, or anywhere with a standard 100–240 V outlet.

The dual-mode trigger system is a genuine production feature. AT mode fires automatically the moment the welding pins make proper contact with the strip — no button press, no foot pedal, just position and touch. For builders assembling hundreds of cells into a large pack, this cuts build time dramatically. MT mode hands control back to the foot pedal, giving you full timing control for debugging a new strip thickness, working in tight quarters, or welding onto an irregular surface.

The 73B mobile welding pen ships with a self-balancing spring mechanism that distributes pressure evenly across both pins — critical for getting consistent weld depth on a cylindrical cell. The 73SA push-down arm locks into the base for stationary work on a flat pack or fixture. Both tools are compatible with 7-series replacement pin system, so consumables are easy to source.

Whether you're building a 48 V e-bike battery, assembling LiFePO4 cells for a solar storage cabinet, or rebuilding a power tool pack, the 801D covers the full nickel-strip welding workflow. It's the right tool for the job — purpose-built for exactly this use case, not an upsell with features you won't use.