![[Pasted image 20250127234538.png]] ## Overview **Description:** High efficiency battery draining system with diagnostics and energy storage **Domain:** Low-power/precision power electronics **Objectives:** - Extract all usable electrical energy from used/"dead" Alkaline Cells (AA, AAA, etc.) - Measure & Log energy extraction data from each cell & deliver analytics - Efficiently convert and push energy extracted into a LiPo power bank Plan is to demo this at Open Sauce in July. **Application Status: Pending** ## Lab Notes (Last Updated: 2025-04-07) ### Research 1. [[Joule Thief - Initial Research]] 2. [[Joule Thief - Basic Simulation]] 3. [[How to wind a toroid inductor]] 4. [[Joule Thief Research 2]] 5. [[IEC Battery Designations]] 6. [[Joule Thief Topologies]] 7. [[AA Cell Hard Limits]] 8. [[AA Cell Hard Limits 2]] 9. [[Load and ESR Investigations]] 10. [[Fast-Drain vs. Slow-Drain]] 11. [[Note - Maximum Power Transfer Theorem]] 12. [[ESR Meter Research]] 13. [[Quick Voltmeter Circuit]] 14. [[Quick Ammeter Circuit]] 15. [[ESR Measuring Circuit Sketch]] 16. [[Dynamic Load - Low R_on FET + Opamp]] 17. [[LV Boost Converter IC Table]] 18. [[LTC3105 - LV Boost Converter]] 19. [[MCP1640 - Battery Boost Board]] 20. [[BMS Design Series]] 21. [[Table of BMS ICs]] 22. [[LTC4015 - Integrated BMS]] 23. [[LTC4015 Battery Management System I2C Signals]] 24. [[BMS Comparison - LTC4015 vs. LTC6804]] 25. [[Multi Channel LTC3105]] 26. [[Supercapacitor Energy Buffer for Intermittent Pulse Charging]] 27. [[Detailed Supercapacitor Charging System for Pulse Charging]] 28. [[Pulse Charge-Discharge Rough Calculations]] 29. **COURSE:** [[Battery Boot Camp Course]] 30. [[Misc. Joule Thief References]] 31. [[LTSpice LT3105 Deeper Dive]] 32. [[LTC3105 Better SPICE]] 33. [[DeepSeek Barebones Discrete BMS]] 34. [[Some Discrete BMS Builds & Parts]] 35. [[Digital Pots to Consider]] 36. [[Cheap MCU Research]] 37. [[Introduction to the ATTiny85]] 38. [[DW01-P Datasheet Annotation]] (new!) 39. [[X9C104 Datasheet Annotation]] (new!) 40. [[Digital Pot Application Circuit Examples]] (new!) 41. [[Quick Note - Setting AD5280 Address]] (new!) 42. [[Some More Layout Vids]] (new!) ### Development 1. [[Joule Thief Build 1]] 2. [[Custom Toroid Inductor Design]] 3. **SIM: [[LTSpice - Random Inductance and Battery Values]]** 4. **SIM: [[LTSpice - Schottky Diode and Capacitor]]** 5. [[Actually winding the First Toroid]] 6. **BUILD LOG:** [[Build Log - Breadboarding the Joule Thief]] 7. [[Joule Thief Waveforms 1.canvas|Joule Thief Waveforms 1]] 8. [[GFM - Battery Holder]] 9. **SIM: [[LTSpice - LTC3105]]** 10. [[Joule Thief MVP sketch]] 11. **BUILD LOG:** [[Build Log - MVP Build Day]] 12. [[Joule Thief - Current State]] 13. **SIM:** [[LTSpice - Rechargeable Battery Simulation]] 14. [[Joule Thief Chips and Bits Purchasing]] 15. **BUILD LOG:** [[Joule Thief Build Day - Pi Mount and Schmitt Trigger Design]] 16. [[Chips on the Amazon BMS]] 17. **SIM:** [[LTSpice - Charge Pulse Energy Delivery]] 18. [[Testing New Amazon BMS and 18650s]] 19. [[Power Constraints - How to Kill a Battery]] 20. [[IRF9540N SPICE Model Generation]] 21. [[DIY Overdischarge Circuit]] 22. [[First Lithium Charge Logs]] 23. [[Alkaline Cell Pulsed Loading Tests]] 24. [[Old Inductor MPPC Settings + Larry]] 25. [[Joule Thief Path Review]] 26. [[New Inductor MPPC Testing + Larry]] 27. [[18650 MPPC Charging Tests]] 28. **DATASHEET:** [[INA219.pdf]] 29. [[INA219 Pop Quiz]] 30. [[INA219 Annotation]] 31. [[Joule Thief R0 - Footprint Hitlist]] 32. [[Joule Thief R0 - Chip Selections]] 33. [[Addressing the Noise]] 34. [[Erratic Behavior on Breadboard]] 35. [[Joule Thief R0 - PCB Super First Draft Notes]] 36. [[Joule Thief R0 - PCB Design Review Points]] 37. [[SMT SPDT PCB Footprint Redraw]] 38. [[SMD Soldering Guide for Joule Thief R0]] (new!) 39. [[Joule Thief R0 Minimal Firmware]] (new!) 40. [[Joule Thief Controlled Input Voltage]] (new!) 41. [[Joule Thief R0 Status, R1 Direction]] (new!) ### Maps [[Joule Thief Maps]] <--- - [[Joule Thief Sketch 0 - Basics.canvas|Joule Thief Sketch 0 - Basics]] - [[Joule Thief Sketch 1 - Full System.canvas|Joule Thief Sketch 1 - Full System]] - [[Joule Thief Sketch 2 - Topologies.canvas|Joule Thief Sketch 2 - Topologies]] - [[Joule Thief Sketch 3 - Expanded System.canvas|Joule Thief Sketch 3 - Expanded System]] - [[Joule Thief Sketch 4 - Processing.canvas|Joule Thief Sketch 4 - Processing]] - [[Joule Thief Sketch 5 - Data Flow.canvas|Joule Thief Sketch 5 - Data Flow]] - [[Joule Thief Sketch 6 - Timeline.canvas|Joule Thief Sketch 6 - Timeline]] - [[Joule Thief Sketch 7 - Master.canvas|Joule Thief Sketch 7 - Master]] - [[Joule Thief Sketch 8 - Tyler.canvas|Joule Thief Sketch 8 - Tyler]] - ![[Joule Thief Weekly 1.canvas]] #### Current Map ![[Joule Thief Sketch 7 - Master 2.png]] ## Misc ### To Do #### Approx. 90 Day Development Timeline Phase 1 - MVP - 2 days Phase 2 - Single-Celled Diagnostics Board - 35 days Phase 3 - Supercap Pulse Charger & BMS Board - 30 days Phase 4 - Database and Frontend on Pi - 14 days Phase 5 - Cell Extraction Array & Extinguish Board - 30 days Phase 6 - Finalization Phase 1 Complete by 2/14? Phase 6 Complete by 5/1? --- #### List 1 - [x] Introduction of the Schottky and Capacitor Load Buffer - [x] Data on the 1N5817, 8, 9 - [x] GPT of Schottky operating principles and key electrical characteristics - [x] Research on Darlington or other Low VBE, Low VCE, High Beta BJTs - [x] Collecting the Ferrite Core Characteristics: - [x] Introduction to the LD1117 - [x] Introduction to the LT1111 - [x] Introduction to the LT1110 - [x] Introduction to the OnSemi MBRS140 and MBR0520L - [x] Recap of GPT - Inductance Winding Calculations - [x] Resistance of Winding Calculations - [x] Recap of GPT - Joule Thief Activation Voltage Explorations - [x] Exploration of Methodologies for Trickle Charging LiPo Batteries from a 5V/5mA source - [x] Slow extraction rate (25mW) means a human could reasonably outperform the thief. - [x] Varying ESR Characteristics of Alkaline Cells - [x] Advantages of Tantalum Capacitors - [ ] LTSpice .meas syntax, data extraction and table creation workflow #### List 2 - [x] See how many Series LEDs I can drive before this thing gets mad at me - [x] Find a way to measure the battery voltage and current at the same time - [x] Set the breadboard up for Test & Measure so I can swap components out - [x] Derive energy efficiency metrics for different circuit/part configurations - [x] Order some second stage modules - [x] Start playing with BMS chips and LiPo Cells, figure out standard charging and trickle charging - [x] Drain a battery completely and see what happens, log some data - [x] Connect a few different loads and see what happens - [x] Start looking into microcontroller-level precision current and voltage metering options - [ ] Once I have some pipelines for harvesting this data, switch to AAA cells - [x] See if I can do anything to kill the battery faster - [x] See if I can do anything to drain the battery as slowly as possible - [x] Compare total energy extracted and energy efficiency metrics for both extremes #### List 3 - [x] Review the design with Tyler - [x] Purchase all the chips in whatever form factor is most convenient - [x] Purchase any additional parts and tools - [x] Find or make SMD to THT breakouts for each of the chips' form factors so I can breadboard the system - [x] Consult Beuter for what solder/flux/etc. and methods to practice given my equipment - [x] Research other BMS chipsets and solutions - [x] Review the BMS boards and designs from previous LiPo battery pack youtube annotations - [x] Design & Order Single-celled Diagnostics board ASAP - [x] Then, Design & Order supercap pulse charger & BMS board ASAP afterwards - [ ] Then, in the time between design and build, learn how to SMD solder. Practice. - [ ] Select and order the Barcode Scanner & Label Printer - [ ] Commission any artwork for the aesthetics - [ ] Build out the Single-Celled Diagnostics Board and begin testing - [ ] Build out the LiPo Battery Bank and begin testing - [ ] Build out the database and software end of the Pi and begin testing - [ ] Design and order the Board for the Cell-Extraction Array - [ ] Design and order the Board for the Cell-Extinguish Module - [ ] Finalize all of the designs and work on the aesthetics and logistics. #### List 4 - [x] Test negative voltage, high frequency methods for battery killing - [x] Learn how to roll my own BMS so I can ensure charging circuit is efficient - [x] Actually charge an 18650 using an AA using the LTC3105 - [x] Rebuild Breadboard circuit with INA219s and the LTC3105 - [ ] Start setting up Pi's UI/Database app #### List 5 - [x] Efficiency Testing with 18650 - [ ] Finish KiCAD Schematic - [x] Set up KiCAD 9 customizations - [x] Read & Annotate INA219 datasheet and set up basic implementation - [x] [[INA219.pdf]] - [x] Confirm symbols & footprints for each part - [x] Organize visually - [x] Layout R0 PCB - [x] Decide what "branch" and "test" features I want to include - [ ] Dummy Load - [ ] Battery Switcher - [x] Mechanical and Electrical Cutoffs - [x] Generic Button, Switches - [x] Addressing Solder Pads - [x] Decide on IO, Battery Holders, Battery Switcher, etc. - [x] Shopping - [x] Inductors - [x] FETs - [x] Schottkys - [x] Switches - [x] Battery Protection ICs - [ ] SoC Monitoring - [ ] Pi UI - [ ] Live Update of metrics - [ ] Persistent Database - [ ] Battery Channel Switching - [ ] Possibly a Node-RED/Interface thing