Build a Precision Li-Ion Battery Spot Welder with Arduino Timing & Safety Interlock

Every part needed, pre-tested for compatibility, with an AI build companion trained on this exact project. Shipped from Bengaluru in 3-5 days.

Assembling a high-current battery pack for an e-bike, solar storage, or a DIY powerwall demands reliable tab connections. This kit turns an Arduino Uno into a capacitor discharge spot welder that delivers controlled, repeatable welds on nickel strips. An ACS712 sensor monitors the actual pulse current in real time, while the safety interlock prevents accidental double-firing — exactly what you need when working with sensitive 18650 cells.

What You'll Build

You will build a tabletop spot welder controller that uses capacitor banks discharged through a relay to fuse nickel tabs onto Li-Ion cell terminals. The OLED displays weld count, pulse duration, and live current readings from the ACS712. Two tactile buttons let you arm and trigger each weld, with an RTC timestamping every weld session for quality tracking.

What You'll Learn

• Design a capacitor discharge circuit for high-current welding pulses
• Program Arduino timing control with relay switching and dead-time prevention
• Interface an ACS712 hall-effect sensor to measure real-time weld current
• Implement a two-button safety interlock sequence to eliminate accidental triggering
• Read and display data on a 0.96-inch OLED, including RTC timestamps

Kit Contents

Why Buy This Kit Instead of Sourcing Parts Separately

Who This Kit Is For

This kit fits B.Tech ECE/EEE students building a semester project on precision welding or power electronics, CBSE Class 12 physics enthusiasts exploring capacitor banks, and Smart India Hackathon teams developing battery assembly prototypes. It is equally useful for ATL Tinkering Labs demonstrating controlled high-current switching and for IIT/NIT/VIT/BITS hobbyists assembling their own e-bike or solar battery packs.

Built and Backed by Compoden

Every Compoden kit ships with an AI build companion trained on this exact project — accessible via a QR code on the box, with WhatsApp and email backup. We've spent 10 years building projects for makers, schools, and institutions across India. If a part fails because of a manufacturing defect, replace it free within 7 days.

Choose your assembly option:

• Soldering Kit — 25W soldering iron, 60/40 solder wire, flux, and small perfboard for permanent assembly.
• Breadboard Combo — 800-point full-size breadboard with 65-piece jumper wire pack for solderless prototyping.