ESP32 Controlled Li-ion Battery Tester

@Mahihassi

With my in-depth understanding of microcontrollers like Arduino and the ESP32, as well as my significant experience in PCB design (including using KiCad), I believe I am tailor-made for this project. Additionally, I hold a Master's in Embedded Systems which has equipped me for tasks akin to this tester's complexities. My knowledge of Circuit Design, Electrical Engineering and proficiency in Electronics further enhances my suitability. The fact that your project requires skills I have honed over the years excites me. My expertise in Microcontrollers which are the heart of your battery tester will ensure operational efficiency and precise temperature-voltage control (essential for Li-ion batteries). Furthermore, I understand that PCB design plays an important role in maintaining efficiency; hence, I guarantee a layout that optimizes space without compromising reliability. By choosing me, you are selecting a freelancer not just to get the job done but someone who genuinely comprehends and shares your passion for electronics. My commitment towards precision and quality-based work combined with my past record of consistently delivering on project targets is something you can trust. Together, let's create an ESP32 Controlled Li-ion Battery Tester that exceeds your expectations!

@macroenergy

Hello there! My name is Metind, and I am excited to offer my extensive dual skill set in electronic design and embedded systems for your ESP32 Controlled Li-ion Battery Tester project. Over the years I have worked on numerous projects involving PCB design and creation of single board embedded systems like the one you require. I understand the importance of getting every small component right, starting from using TP4056 or MCP73831 for optimal charge to selecting 3R9 10 W non-inductive resistors for accurate discharge. In addition, my diverse experience extends to implementing state-of-the-art sensor modules such as INA219/228/260 utilizing an I²C interface for data acquisition and integrating the measured values into lasting results such as total mAh. Precise data interpretation is key to achieving your goal of logging capacity efficiently; something that I definitely bring to the table. I am also familiar with using WS2812 RGB LEDs for visual representation as required in your project, tying everything together seamlessly. Fusion 360 & KiCAD are tools in my wheelhouse; I ensure an orderly schematic and PCB design while following your layout needs of a ≤100 × 150 mm board with all components on a single side if possible.

@AITSoft

Hello, I understand that you're looking for a 1-board, 4-channel Li-ion battery tester using an ESP32, which will handle charging, discharging, and logging capacity while providing JSON output over USB. My approach will involve designing a schematic and PCB layout that meets your specifications while ensuring efficient power management and accurate logging with the specified components. I will provide firmware that handles the cell detection, charging, discharging, and outputting the necessary JSON data, along with a detailed README to assist in setup and testing. What are your specific requirements for the communication protocol over USB? Thanks, Shamshad

@cpp2048

If you need to design a commercial product, I can help. I made similar battery tester long time ago to plot discharging curve of batteries of different types and make and if contacted I can show you interesting plots. To design a robust system TP4056 is not the choice. This is linear type charger and not very reliable, On the other hand, discharging through 3.9ohm resistor is not the right choice mainly because, it's quite difficult to extract heat efficiently from these resistor. Even forced cooling can't be efficient either. I am not sure if you made these choices to minimize the product cost or just for simplicity. My bid, however, includes through product testing and validations. If you still want to stick to the same plan, we can negotiate on the price. Thank you

@AwaisChaudhry

Hello, I understand you need a compact, 4-channel Li-ion battery tester utilizing an ESP32. My approach will focus on integrating the charging and discharging components effectively while ensuring accurate data logging and user-friendly interfaces. I will design the schematic and PCB with attention to your specifications, like component placement and thermal management, ensuring it meets all requirements for a seamless user experience. I will also provide well-documented firmware that includes a state machine to manage the device’s operation and log data in JSON format for easy access. My experience in Arduino programming and PCB layouts will ensure that your project is executed with precision and efficiency. What are the specific parameters you have in mind for battery capacity logging and data display requirements? Thanks, Muhammad Awais

@markoa7

Hello, I am eager to collaborate on the 4-Channel Automated Battery Tester project using my expertise in ESP32 hardware and firmware design. With proficiency in Fusion 360 and the Arduino framework, I will design a compact system meeting your requirements. The project will include charging/discharge monitoring via INA219, controlled by an ESP32 with status updates on RGB LEDs and JSON output. I will deliver a complete schematic, PCB layout, and tested firmware, accompanied by thorough documentation. My experience with ESP32 and PCB design tools ensures a reliable and efficient solution tailored to your needs. Looking forward to bringing this vision to life. Best regards, Marko A.

@Adeel2k14

We are a team of embedded engineers with 6+ years of experience in PCB design (up to 8 layers, mixed-signal, power, and analog) and firmware development. We will deliver a 4-channel Li-ion tester using ESP32 with accurate charging/discharging control, INA260-based current sensing, RGB status indicators, and JSON logging over USB. Deliverables include a well-documented Fusion 360 or KiCad design, BOM, Gerbers, and Arduino firmware with a state-machine. We ensure reliable performance and clean integration within a compact PCB layout.

@PCBDESIGNER38

With over 6 years of experience in PCB design and a deep understanding of your project's requirements, I firmly believe I'm the right freelancer for this. My extensive experience in developing electronic hardware, including IoT devices and power electronics, gives me a unique perspective when it comes to designing your ESP32 controlled Li-ion battery tester. Moreover, I have the proficiency using various CAD software including Fusion 360 and KiCad, so delivering the schematic and PCB designs under 100 × 150mm won't be a challenge. I understand the need for precision in your project; hence I always adhere to signal and power integrity best practices while designing PCBs. Additionally, I bring strong simulation skills using tools such as LTSpice and PSpice to your project ensuring circuit validation for optimal functionality. My commitment to collaborative work has been proven through my effective coordination with firmware and MCAD teams in previous projects which is essential for the success of an integrated system as yours. In hiring me you would gain a real partner who values open communication, met deadlines, cost efficiency and confidentiality- all elements that are important to your project. Let's transform your vision into sturdy schematics, BOMs and Gerbers and ultimately bring forth a reliable Li-ion battery tester that meets every single aspect of your description. Invite me to be part of your project today!

@TopRated209

Hello sir, I’m excited to submit my proposal for your 4-channel Li-ion battery tester project. With my expertise in ESP32-based hardware design, BLE systems (e.g., smart locks using similar components like INA219 and WS2812 LEDs), and Fusion 360/KiCad PCB development, I’m confident I can deliver a reliable, compact, and fully documented solution that meets your requirements. Why Choose Me? ✅ Proven Experience: Designed ESP32-based BLE smart locks using INA219 (I²C current sensing), WS2812 LEDs, and TP4056 charging circuits — identical to your project’s core components. ✅ Hardware-Software Integration: Expert in ESP32 (Arduino/PlatformIO) for state-machine control. ✅ End-to-End Delivery: Full schematic + PCB design (Fusion 360/KiCad). Production-ready Gerbers + BOM. Proposed Solution Hardware Design Single PCB (≤100×150mm) with: 4x JST-PH 2.0mm battery inputs (front-edge placement). TP4056/MCP73831 per channel (1.2A CC/CV charging). 3R9 10W resistors + AO3400 MOSFETs (1A discharge load). INA219 (I²C 0x40–0x43) for current/voltage monitoring. WS2812 RGB LEDs (series chain, ESP32-controlled). Polyfuses + TVS diodes for protection. Always-on 5V fan header (2-pin, 500mA max). Deliverables ✅ Schematic + PCB (KiCad/Fusion 360, one-sided placement). ✅ Gerbers + BOM (JLCPCB-compatible). ✅ Firmware (PlatformIO/Arduino, commented). ✅ README (flashing, wiring, testing). Ready to start immediately. Let’s discuss! Best regards,

@kkirandeep582

Having worked in the electronics industry for over 8 years, I'm confident that I am the right person for your ESP32 Controlled Li-ion Battery Tester project. My deep expertise in circuit design and PCB layout, especially using tools like Fusion 360 and KiCad, makes me proficient in meeting PCB space constraints while ensuring adequate component placements and copper tracks for optimum performance. I have previously designed similar multi-channel battery testers with functionalities including charging, discharging, and logging, which makes me well-versed with incorporating appropriate components such as TP4056 or MCP73831 for charging and non-inductive resistors with N-MOSFETs like AO3400/IRLZ44N for discharge. Your specific requirements of incorporating TP4056/MCP73831, INA219/228/260 sensors and WS2812 RGB LEDs can be handled efficiently given my prior experience. Finally, apart from designing the schematic and PCB layout and generating essential deliverable such as Gerbers and BOMs, my diverse skill set extends towards programming as well. I can comfortably develop the firmware sketch you've outlined with its various conditions while also ensuring thorough documentation (in line with your README specifications) to facilitate future usage of the system.

@Ahmed8033

Hi there, This project perfectly matches my expertise in embedded systems and PCB design. I have strong experience working with ESP32, INA219, WS2812 LEDs, and TP4056 modules. I can design your 4-channel battery tester using KiCad, and develop clean, reliable firmware using the Arduino framework—complete with state machines, JSON output, and LED indicators as required. I’ll ensure high-quality hardware and firmware with detailed documentation, ready for manufacturing and testing. Let’s connect to discuss your needs in more detail—I’m ready to start! Best regards, Ahmed

@engrusmanfaiz

Hi, This looks like a solid project—I’ve built similar multi-channel testers and battery monitoring setups using ESP32 and INA sensors. I can design the PCB with all four channels, charging/discharging logic, and protections, keeping everything compact and clean. Firmware will be efficient and modular, logging capacity, pushing JSON over USB, and handling state transitions clearly. I’ll use KiCad or Fusion 360, and make sure the board is easy to assemble, with proper silk and thermal layout. Happy to provide full documentation, source files, and test instructions. Let’s bring this to life! Best regards, Engr. Muhammad Usman

@ozdemirmcihad

Hello, As an R&D Manager with over 8 years of embedded hardware/software experience, I specialize in ESP32-based systems, battery management, and precision current sensing. Your 4-channel Li-ion tester project aligns perfectly with my core competencies. ? Battery Handling: I’ve designed multi-cell Li-ion charge/discharge boards using TP4056, MCP73831, and MOSFET-controlled resistive loads. I can ensure accurate CC/CV charging and stable 1A discharge using thermal-optimized resistor placement and MOSFET switching logic. ? ESP32 Firmware (Arduino/PlatformIO): Modular state machine: detect → charge → rest → discharge → report I²C management for INA219/260 sensors (0x40–0x43), sampling every 1–2s JSON reporting over USB Serial + RGB status (WS2812) updates Efficient mAh integration with temperature-aware safety logic ? PCB Design (KiCad): Single-sided layout, ≤100×150 mm Clean silkscreen, JST-PH headers, proper copper clearing under 10W resistors ESD/TVS + polyfuse protection + clear polarity markers ? Deliverables: KiCad Schematic + PCB + BOM + Panelized Gerbers Fully documented firmware with build & flash instructions Easy-to-follow README with test + hookup procedure I can begin immediately and deliver a robust and reliable prototype, optimized for both safety and usability. Let’s bring this precision tester to life. Best regards,

@electronicsdone

Best Battery Tester Hardware Design Expert! ⭐⭐⭐⭐⭐ Dear Trent, I can help you develop a reliable, compact, and thermally balanced 4-channel Li-ion battery tester with precise capacity logging, JSON reporting, and RGB status feedback—all on a single, production-ready PCB. With 30+ years of experience in battery-powered systems, ESP32-based control, and heat-managed PCB design, I specialize in test and measurement tools like this. ✅ 1. Valuable Suggestion: To maximize measurement accuracy, I recommend spacing INA219s and discharge resistors to reduce thermal crosstalk and using a ground-symmetric layout to minimize I²C drift from switching noise during discharge cycles. ✅ 2. Similar Projects: 1. 6-channel 18650 analyzer with USB data logging and WS2812 state LEDs 2. ESP32-controlled battery balancer with load/charge management logic 3. Multi-cell Li-ion test jig with thermal copper pour zones and isolated I²C current sensing ✅ 3. What You’ll Get: 1. Clean schematic and PCB layout (KiCad or Fusion 360) with labeled silkscreen 2. Discharge-safe copper areas under load resistors with thermal spacing 3. BOM, Gerbers, and JST-aligned layout (≤100×150 mm, one-sided assembly) ✅ 4. Quick Question: Would you prefer using INA219 for cost or INA260 for built-in shunt accuracy and reduced layout complexity? Let’s build a robust, production-ready battery tester that’s reliable, safe, and easy to scale. Best regards, PCB Must Innovations

@shykhAbubakar

Hello, I have reviewed provided document and can assist you in designing a compact, multi-channel Li-ion battery tester based on ESP32 that meets your outlined specifications. The solution will comply with best practices in embedded hardware and firmware design, using IPC standards for PCB layout and ANSI C/C++ for embedded development. Following are the deliverables: • Schematic design and PCB layout • Gerber and Drill files for manufacturing • Firmware development • Detailed list of BOM I wanted to ask: • Do you prefer MCP73831 or TP4056 for charging (one has smaller footprint, the other includes protection)? I have 7+ years of experience in similar projects like: • Smart battery analyzers and balancers • ESP32-based IoT sensor boards with OLED, INA219, and RGB indicators • Modular power boards for lithium battery testing using similar current profiles I am proficient in software’s like: • KiCAD, Fusion360, Altium Designer, EAGLE • PlatformIO, STM32Cube IDE Thank you for considering my proposal. Looking forward to collaborating with you on this project. Best Regards, Abubakar

@vladyslavv3

Hello. I can deliver a compact 4-channel Li-ion tester with full ESP32-based control, USB JSON logging, and color-coded WS2812 status indicators—optimized for charge/discharge cycles and accurate capacity logging using INA219 sensors. With experience designing robust one-sided PCBs and integrating high-current battery paths with protection and thermal management, I’ll provide a complete hardware + firmware solution, including schematics, gerbers, BOM, and a well-documented state-machine firmware. Let’s build a reliable, USB-powered Li-ion test board that’s practical, safe, and extensible. Please contact me. Best regards, Vlad.

@Mahmoud00Ibrahim

Hi, I'm an embedded systems and hardware design engineer with hands-on experience in ESP32-based projects, battery management systems, and I²C sensor integration. I can deliver your 4-channel Li-ion battery tester project from schematic to firmware, ensuring reliable charge/discharge cycles, accurate mAh calculations, and clear JSON logging via USB. What I bring: Proficiency in ESP32 (Arduino/PlatformIO) Experience with TP4056, INA219, and MOSFET-based loads Compact, single-sided PCB design (KiCad/Fusion 360) Optimized I²C handling and LED status integration (FastLED or Adafruit_NeoPixel) Clear firmware architecture using a modular, commented state machine I've built similar test rigs for lithium cells and power analysis tools with real-time monitoring. I'll also ensure proper protection (polyfuses, TVS/Schottky), robust fan/power integration, and a clean silkscreen layout for usability. You’ll receive the full design files, ready-to-build firmware, and a well-documented README covering hookup, flashing, and operation. Let’s bring this tester to life. Best regards,

@isurutech

Dear Sir, I would like to present myself as prospective candidate to do your project. I have sound knowledge and experiences in Electronic and Programming. Including PCB design and ESP32 programming. I have read your project description and I could present myself as most suitable candidate to do your project as my skills are align with your project requirement. I have good experience in design PCB with using KiCAD. If you visit my profile you will see many of my PCB designs. Also have good experiences in programming ESP32, for programming of ESP32 I prefer Arduino IDE. regarding the project design description and requirement everything is explained perfectly. Regarding rest time after charge, dose the rest time is fixed with code or do need to update via USB ? Expecting a favorable reply, I remain. Isuru Athukorala

@redbrickamerica

Hello there! I am ready to take on the project for the ESP32 Controlled Li-ion Battery Tester. The goal is to create a 4-channel Li-ion tester using a single ESP32. The design includes charging, discharging, capacity logging, and JSON output over USB. The system will feature RGB indicators for status. The project requires skills in Arduino, Embedded Systems, PCB Layout, Electronics, Circuit Design, Fusion 360, Electrical Engineering, and JSON. I will deliver schematic, PCB design, Gerbers, BOM, firmware with a state-machine, and comprehensive README instructions. Let's create a robust and efficient battery tester together! What specific requirements or preferences do you have for the firmware and PCB design? Cheers, RedBrick American Engineering