Battery charge level indicator Li-Ion/Li-Po 2S with LED display

Battery charge level indicator Li-Ion/Li-Po 2S with LED display

A compact charge level indicator designed for precise monitoring of 2S Li-Ion and Li-Po packs. The module enables accurate voltage tracking in the range from 6.6V to 8.4V. It features a clear, 4-step LED display that reports the current battery capacity in real time.

Key technical specifications

• Power supply: directly from the measured source
• Measured voltage range: 6.6V - 8.4V
• Current draw: 2mA - 6mA
• LED indicator: 4-step (blue segments, red border)
• Refresh rate: 500 ms per measurement (1 Hz)
• Operating temperature: 10°C to 65°C
• Overall dimensions: 44 x 20 x 9 mm
• Screen dimensions: 31 x 20 mm

Charge levels on the display

The device clearly shows battery status using illuminated segments:

• 4 segments (100%) - battery voltage above 7.8V
• 3 segments (75%) - battery voltage 7.4V - 7.8V
• 2 segments (50%) - battery voltage 7.0V - 7.4V
• 1 segment (25%) - battery voltage 6.6V - 7.0V
• 0 segments (0%) - battery voltage below 6.6V (only the red border lights up, indicating deep discharge)

How it works

The indicator continuously analyses the voltage of the connected pack. Each of the four internal display segments lights up in blue, proportionally to the charge level. The outer red border serves as a warning-when it lights up on its own, it signals that the voltage has dropped below the safe threshold of 6.6V. With refresh every 500 ms, readings are smooth, and the low current draw of around 2mA - 6mA does not significantly load the monitored battery.

Example applications

• Monitoring power in RC models (cars, boats, drones)
• Battery status checks in portable Bluetooth speakers
• Charge indicator in hobby robotics projects
• Emergency power systems based on 2S packs
• Custom portable electronics builds (DIY)

Benefits

• Instant battery status assessment thanks to a clear, backlit interface
• Cell safety through clear indication of deep discharge
• Easy installation thanks to the module’s compact size (44 x 20 mm)
• Energy efficiency ensured by very low current consumption
• Versatility for use with popular Li-Ion and Li-Po cells in 2S configuration