Solar Home Battery Manager Kit with ESP32 + Relay
Build a Home Solar Battery Manager with ESP32, MPPT & Automated Load Shedding
Every part needed, pre-tested for compatibility, with an AI build companion trained on this exact project. Shipped from Bengaluru in 3-5 days.
Imagine a compact, wall-mounted controller that draws every possible watt from a 6V solar panel, feeds it intelligently into a 4-cell 18650 battery bank, and — the moment the battery dips dangerously low — automatically disconnects non-critical loads via four relays. This kit lets you build that exact system, complete with real-time monitoring on an OLED and data logging to microSD. It’s not a toy demo; it’s a functional power manager that could one day run your off-grid sensor nodes or backup lighting circuits.
What You'll Build
You’ll assemble and program an ESP32-based charge controller that implements a custom Maximum Power Point Tracking (MPPT) algorithm. Two INA219 high-side current sensors measure solar input power and battery charge/discharge simultaneously. When battery voltage falls below a programmable threshold, the 4-channel relay module sheds loads in priority order, protecting 18650 cells from deep discharge damage. An RTC timestamps all events, and the OLED displays live current, voltage, power, and state-of-charge.
What You'll Learn
- Implement a real-time MPPT perturb-and-observe algorithm on ESP32 to maximize solar harvesting
- Interface dual INA219 sensors over I2C for simultaneous voltage, current, and power monitoring
- Design load-shedding logic using relay drivers and battery state-of-charge estimation
- Log system telemetry onto microSD with DS3231 RTC timestamps for later analysis
Kit Contents
| Component | Quantity |
|---|---|
| ESP32 Dev Board | 1 |
| INA219 | 2 |
| Solar Panel 6V 2W | 1 |
| 18650 Cell | 4 |
| TP4056 Module | 1 |
| LM2596 Buck Converter | 1 |
| 4-ch Relay Module | 1 |
| 0.96in OLED | 1 |
| DS3231 RTC | 1 |
| MicroSD Module | 1 |
| 100nF Caps | 10 |
| PCB Prototype Board | 2 |
| 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
This advanced kit is built for B.Tech ECE/EEE students tackling final-year projects or Smart India Hackathon prototypes that demand real power electronics and IoT integration. It’s equally suited for ATL Tinkering Lab instructors mentoring competitive teams, and for serious hobbyists at IIT, NIT, VIT, or BITS Pilani who want to move beyond Arduino blink routines into embedded systems that manage real energy flows. If terms like I2C address conflict and relay flyback diodes don’t scare you, you’ll find this project deeply rewarding.
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 to open a detailed walkthrough and an AI assistant that replies with code snippets, wiring corrections, and algorithm tweaks specific to this kit. Same-day WhatsApp backup is available for hardware issues.
Does this kit include a battery protection BMS?
The TP4056 handles single-cell charging and discharge cut-off. For the 4-cell bank you’ll connect it through the buck converter, but over-discharge and load-shedding logic is handled by the ESP32 via relay control. You’ll code the state-of-charge estimation yourself using INA219 readings.
Can I scale this to a larger solar panel?
The LM2596 buck converter can handle up to 40V input, but the kit’s 6V 2W panel matches the TP4056’s input limits. For larger panels, you’d replace the charging module and adjust MPPT parameters — the ESP32 code is extensible, and our AI companion can guide modifications.
Is soldering required, and is an iron included?
Yes, the kit includes a basic soldering iron and solder wire. You’ll solder components onto the prototype PCBs and make reliable connections. Full soldering tips for the specific pads are part of the build guide.
INA219 monitors solar and battery. MPPT on ESP32 maximises charging. Relay load shedding on low battery.
What's in this kit
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