Powering Up the AetherBeam — Custom 1S2P Li-Ion Packs!

🧠 Overview

This bench session focused on building custom 1S2P lithium-ion battery packs using a precision spot welding setup. While originally intended for a separate project, the configuration proved to be an excellent fit for the Aetherbeam LED system—delivering high capacity in a compact form factor.

🎯 Objective

Design and assemble a high-capacity, compact battery pack that:

• Maximizes runtime for LED applications
• Maintains a clean, space-efficient layout
• Ensures safe and reliable operation

🛠 Tools & Technologies

• FNRISI SWM-10 spot welder
• Samsung 35E 18650 lithium-ion cells (3500mAh each)
• Pure nickel strip (for conductivity and durability)
• XT-style balance leads
• 3D-printed battery alignment jig
• Multimeter (for validation and testing)

⚙️ Process

1. Pack Configuration

A 1S2P configuration was selected:

• 1 series group (nominal 3.7V)
• 2 cells in parallel for increased capacity

This results in a combined capacity of approximately 7000mAh, ideal for extended runtime applications.

2. Cell Preparation & Alignment

• Cells were inspected and matched for consistency
• A custom 3D-printed jig was used to maintain alignment during assembly
• Layout was optimized for both compactness and structural stability

3. Spot Welding Assembly

• Nickel strips were spot welded to create solid electrical connections
• Heat exposure to cells was minimized compared to traditional soldering
• Weld consistency ensured reliable conductivity across the pack

4. Lead Integration

• XT-style leads were prepared and positioned for clean integration
• Connections were verified prior to final assembly

🚧 Challenges & Solutions

Challenge: Maintaining precise alignment during welding
Solution: Designed and used a custom 3D-printed jig to hold cells securely in place

Challenge: Avoiding heat damage to lithium-ion cells
Solution: Used spot welding instead of direct soldering to reduce thermal stress

Challenge: Balancing compact design with usability
Solution: Optimized layout to fit within Aetherbeam constraints without sacrificing accessibility

📊 Results / Outcome

• Achieved ~7000mAh capacity using Samsung 35E cells
• Clean, compact battery pack suitable for integration into Aetherbeam
• Reliable weld quality and consistent electrical performance
• Improved projected runtime for LED applications

🔄 Improvements / Next Steps

• Integrate full BMS for enhanced protection
• Design a sealed enclosure for outdoor/weather resistance
• Explore modular battery swapping options
• Release STL files for the battery jig and enclosure

📸 Visuals

💭 Takeaways

Building custom lithium-ion packs highlights the importance of precision, safety, and repeatability.
Using proper tools like a spot welder and alignment jig significantly improves both build quality and reliability.

This project reinforces the value of designing systems holistically—where power, form factor, and usability all need to work together.