battery-selector_skill

Overview

This skill helps you choose the right battery chemistry and charging solution for Arduino, ESP32, and RP2040 projects. It guides selection based on voltage, current, runtime, safety, and form factor to match your MCU and peripherals. The goal is practical, safe recommendations that prevent brownouts, overcharge, and dangerous misuse.

How this skill works

I inspect your project requirements—average and peak current, required runtime, nominal voltage, physical constraints, and whether rechargeability is needed. I then map those needs to suitable chemistries (Alkaline, NiMH, LiPo, LiFePO4, coin cells) and recommend regulation and charging circuits (LDO, boost, TP4056, balance chargers). I also provide sizing calculations, safety checks, and wiring/connector best practices to avoid common failures.

When to use it

• You ask “what battery should I use” for a portable MCU project
• Choosing a charger or charging module for LiPo/NiMH
• Designing power for ESP32/RP2040 or Arduino with WiFi or sensors
• Sizing battery capacity for a required runtime
• Evaluating trade-offs: weight, cost, safety, and availability

Best practices

• Calculate average current and include a 1.25 safety factor when sizing mAh
• Design for peak current (WiFi TX, motors) not just average; add bulk capacitance to prevent brownouts
• Use protection-equipped charging modules (TP4056 with protection or PowerBoost) for LiPo
• Prefer LiFePO4 for safety-critical or long-life deployments; use LiPo for weight-sensitive builds
• Never charge LiPo with improvised supplies; follow CC-CV, temperature, and C-rate limits

Example use cases

• Low-power sensor node: single LiPo or 18650 with deep sleep, TP4056 charger, capacity sized from average current
• Handheld device: flat LiPo 1000–2000mAh plus boost converter or PowerBoost for 5V systems
• Robot/high-current: 2S/3S LiPo pack with balance charger and buck regulator to 5V
• Ultra-low-power beacon: CR2032 or 2×AA primary cells with no charger for multi-month runtime
• Solar-backed remote: LiFePO4 plus MPPT charge controller for rugged outdoor deployments