Custom Power Bank |3| Requirements
Intro
This series of notes describes developing process of custom power bank.
Purpose: listing expected specification and other requirements for future custom power bank.
Mandatory and desired requirements
- 🟢 Mandatory
- 🔵 Desired
Prototype Visualization
| MY | AI |
 |  |
Requirements
| Requirement Name | BASIC Version | ELITE Version | |
CELLS | |||
| Cells size | 18650 and/or 21700 | 🟢 Mandatory | |
| Cells connection type | Holder (THT/SMD) | 🟢 Mandatory | |
| Cells connection | Parallel only | 🟢 Mandatory | |
| Number of cells (holder) | up to 3 | 🔵 Desired | |
| Number of cells (pack) | up to 4 | 🔵 Desired | |
| Calls additional connector for pack | Optional battery connector (DNP, 5A+) or wires soldering | 🔵 Desired | |
| Expected electrical capacity | Depends of cells (e.g. 18650: 3400mAh, 21700: 5000mAh): 3P1S 18650 Holder: 10200 mAh (37.74W) 4P1S 18650 Pack: 13600 mAh (50.32Wh) 3P1S 21700 Holder: 15000 mAh (55.5Wh) 4P1S 21700 Pack: 20000 mAh (74.0Wh) | 🔵 Desired | |
BUTTONS | |||
| IP Button | KEY | 🟢 Mandatory | |
| User buttons | - | USER BUTTON 1 USER BUTTON 2 USER BUTTON 3 USER BUTTON 4 | 🔵 Desired |
POWER PORTS | |||
| USB connectors (ports) | USB-A OUT USB-A OUT USB-C IN USB-C IN/OUT | 🟢 Mandatory | |
| Charging and discharging with fast protocol at the same time | Yes (need two IC) | 🟢 Mandatory | |
| UPS support | Seamless power providing | 🟢 Mandatory | |
PCB | |||
| Components size | 0603 or bigger (for easy repair) | 🟢 Mandatory | |
HOUSING | |||
| Top cover | Transparent Top Side (3mm acrylic) | 🟢 Mandatory | |
| Case | Plastic (3D Printed) | 🟢 Mandatory | |
| Clip | On the back side (optional) | 🔵 Desired | |
| Carabiner or strap support | Yes | 🔵 Desired | |
| Magnets | Magnets of the bottoms side of case | 🔵 Desired | |
LIGHT | |||
| Light | LEDs connected to the IP IC (Warm Light) | 🟢 Mandatory | |
CONTROLLER | |||
| Microcontroller | - | ESP MCU | 🔵 Desired |
| Debug/programming | - | UART | 🔵 Desired |
| Firmware update | - | OTA | 🔵 Desired |
DISPLAY | |||
| Display | - | IPS Color Display | 🔵 Desired |
POWER MEASUREMENT | |||
| Current and Voltage Measurement | - | Yes, for each USB and BAT (5 in total) | 🔵 Desired |
NOTIFICATORS | |||
| RGB Indicator LED | - | RGB LED | 🔵 Desired |
| Sound Beeper | - | Buzzer | 🔵 Desired |
OTHER SENSORS | |||
| Battery Temperature Sensor | IP Temperature Sensor | 🔵 Desired | |
| Onboard IP IC Temperature Sensor | - | Digital I2C Sensor | 🔵 Desired |
| Ambient Temperature Sensor | Digital I2C Sensor | 🔵 Desired | |