Arduino Mega Battery Formation Cycler - Characterize 18650 Cells at C/5 Kit
Arduino Mega Battery Formation Cycler - Characterize 18650 Cells at C/5
Every part needed, pre-tested for compatibility, with an AI build companion trained on this exact project. Shipped from Bengaluru in 3-5 days.
Build a reliable tool for matching lithium-ion cells. When constructing battery packs for drones or EVs, every cell must be formation-cycled to measure its real capacity. This kit automates three charge-discharge cycles at a C/5 rate, logging capacity via dual INA219 sensors, so you can select cells with identical performance.
What You'll Build
A standalone formation cycler that charges an 18650 cell through a TP4056, then discharges it through a constant-current load (MOSFET and 10? resistors) while monitoring voltage and current. After three full cycles, the OLED displays the cell's average discharge capacity, and all data is saved to a microSD card with timestamps from the DS3231 RTC.
What You'll Learn
- Programming an Arduino Mega to manage multi-step charge/discharge sequences
- Interfacing dual INA219 current sensors over I2C using a TCA9548A multiplexer
- Building a constant-current discharge circuit with MOSFET and power resistors
- Logging experimental data to microSD with precise timestamps for later analysis
Kit Contents
| Component | Quantity |
|---|---|
| Arduino Mega 2560 | 1 |
| INA219 | 2 |
| TCA9548A I2C Mux | 1 |
| IRF540N MOSFET | 1 |
| TP4056 Module | 1 |
| 18650 Cell | 4 |
| DS3231 RTC | 1 |
| MicroSD Module | 1 |
| 0.96in OLED | 1 |
| 10? 5W Resistors | 2 |
| 100nF Caps | 10 |
| PCB Prototype Board | 3 |
| Soldering Iron | 1 |
| Solder Wire | 1 |
Why Buy This Kit Instead of Sourcing Parts Separately
| Factor | Sourcing Separately | Compoden Kit |
|---|---|---|
| Compatibility checks | You verify every part | Pre-tested as a system |
| Build support | Forums and scattered tutorials | AI companion trained on this exact project |
| Time to first working build | Days of debugging | Hours, with step-by-step guidance |
| Shipping coordination | Multiple sellers, multiple delays | One shipment from Bengaluru in 3-5 days |
Who This Kit Is For
Ideal for final-year B.Tech ECE/EEE students building EV battery management systems as capstone projects, teams preparing for Smart India Hackathon energy storage challenges, and ATL Tinkering Lab mentors teaching advanced lithium-ion characterization to senior students. Also suits IIT/NIT/VIT undergraduates needing precise cell matching for drone or robotics 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.
What if I get stuck during the build?
Scan the QR code on the kit box to chat with our AI companion trained on this exact project; it can walk you through wiring, code debugging, and calibration. If you need human help, message us on WhatsApp and an engineer will respond within 24 hours.
Does the kit include the 18650 cells to be cycled?
Yes, four new unprotected 18650 cells rated at 2600mAh are included, so you can start characterizing immediately.
Can I use this cycler with other lithium chemistries like LiFePO4?
The default software is calibrated for 4.2V 18650 cells, but you can modify the charge and discharge cut-off voltages in the Arduino code to accommodate LiFePO4 or other chemistries.
What is the discharge current and how accurate is the capacity measurement?
The constant-current discharge is set to C/5, around 520mA for the included cells, using 10? resistors biased by the MOSFET. The INA219 sensors provide �1% current and voltage accuracy, and the system computes capacity in mAh by integrating discharge current over time, logged to SD card.
Charges then discharges 18650 cells at C/5 rate three times. INA219 measures capacity each cycle for formation.
What's in this kit
- Arduino Mega 2560
- INA219 x2
- TCA9548A I2C Mux
- IRF540N MOSFET
- TP4056 Module
- 18650 Cell x4
- DS3231 RTC
- MicroSD Module
- 0.96in OLED
- 10? 5W Resistors x2
- 100nF Caps x10
- PCB Prototype Board x3
- Soldering Iron
- Solder Wire
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.
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Shipping Information
- Prepaid Orders: ₹75 for orders up to ₹999, FREE shipping above ₹999
- COD Orders: ₹125 shipping + ₹50 COD fee = ₹175 total
- Delivery Timeline: Dispatch in 1-2 days, delivery in 2-7 days depending on location
Returns & Warranty
- 7-Day Return: Manufacturing defects only (approval required)
- Warranty: 7 days from delivery
- Non-Returnable: Batteries, consumables, cut wires, clearance items