Mini Battery Level Indicator Module | 1S 2S 3S 4S Series Battery Meter | Lithium Battery Percentage Display Module

Features1. Supports 1S–4S lithium battery series configurations with strong compatibility2. Accurately displays battery percentage for intuitive and easy-to-read readings3. Ultra-compact design, easily integrated into compact devices4. Low-power operation, extending the device’s standby time5. Manual series configuration switching, convenient to useParameterMaximum Voltage Rating: 36V ±10%Voltage Measurement Range: 3–17.29VBattery Capacity: UnlimitedBattery Level Display: 0%–100%Measurement Accuracy: ±1%Average Operating Current: 7mA ± 0.3mARefresh Rate: 0.3 seconds per updateOutput Control: NoneReverse Polarity Protection: None (Positive and negative terminals must not be reversed; doing so will damage the module)Compatible Battery Range: The module is compatible with all lithium battery packs consisting of 1 to 4 cells in series or parallel configuration with a rated voltage of 3.7V (full charge voltage 4.2V); this includes 14500, 18650, 21700, polymer lithium batteries, and other batteries of any capacity or sizeModel with Smart ButtonFeatures a smart button. Upon power-up, the device first detects the number of battery cells; at this point, it defaults to Mode 0. The display lights up after approximately 1 second and shows the current battery percentage. A short press (less than 3 seconds) of the smart button serves as the power on/ function; a long press (over 3 seconds) activates the mode switching function, allowing you to switch to Mode 1. After switching to Mode 1, the display turns off by default. A short press (within 3 seconds) of the smart button immediately turns the display on, and the value rises from 0% to the normal battery level within approximately 1 second (since the button functions are shared, the filter capacitor needs to charge after power-up), then automatically turns off after a 3-second delay. A long press (>3 seconds) serves as the mode-switching function, allowing you to switch back to Mode 0, and the cycle repeats;Precautions1. Connect VCC to the battery’s positive terminal and GND to the battery’s negative terminal; these are labeled on both the front and back of the board. As shown in the wiring diagram, facing the battery meter, the pads are on the left—the top is positive and the bottom is negative;2. Ensure the power is off when wiring; otherwise, accidentally touching the pins on the back of the board may cause a short circuit and damage the module. After soldering, verify that the positive and negative terminals do not touch the pin pads on the back of the battery meter before powering on;3. There is no reverse polarity protection; connecting the positive and negative terminals incorrectly will damage the module. It is recommended to verify the polarity before wiring;4. Not compatible with 3.2V lithium iron phosphate (LiFePO4) batteries or lead-acid batteries. During charging, the charger raises the battery voltage, causing the displayed charge level to be approximately 110% higher than the actual charge. The exact increase depends on the charging current and the battery’s internal resistance; this is a normal phenomenon!Package includeModule *1