Li-Ion/Li-Po 3S Battery Charge Level Indicator with LED Display

Li-Ion/Li-Po 3S Battery Charge Level Indicator with LED Display

This charge level indicator was designed for precise monitoring of 3S Li-Ion/Li-Po packs. Thanks to its reliability and accuracy, it is an ideal tool for applications where tracking voltage in the 11.1 - 12.6V range is required.

Key technical specifications

• Measuring range: 11.1 - 12.6V
• Power supply: drawn directly from the measured source
• LED indicator: 4-level, easy-to-read display
• Refresh rate: 500ms per reading
• Operating temperature: -10°C to 65°C
• Dimensions: 44 x 20 x 9.2 mm
• Block backlight color: blue
• Battery outline backlight color: red

Backlight levels and function description

The indicator features a 4-level LED display that accurately reports the battery charge level. Each level is indicated by a corresponding number of blue blocks:

• Below 9.9V: 0 blocks - indicates a very low charge level. The red outline also lights up as a clear warning signal before deep discharge.
• 9.9V - 10.5V: 1 block - battery at 25% charge.
• 10.5V - 11.1V: 2 blocks - battery at 50% charge.
• 11.1V - 11.7V: 3 blocks - battery at 75% charge.
• Above 11.7V: 4 blocks - battery fully charged.

Compact dimensions make it easy to install the module in various enclosures and devices. The module provides precise charge state monitoring across a wide temperature range.

Example applications

• Monitoring battery state in RC models (cars, drones, boats).
• Power control in portable DIY Bluetooth speakers.
• Charge indicator in backup power systems and power stations.
• Diagnostic tool in electronics and robotics workshops.
• Monitoring element in projects powered from 3S packs.

Benefits

• Instant battery status assessment thanks to a clear, graphic LED interface.
• Cell protection - the red outline immediately warns of a dangerous voltage drop below 9.9V.
• Easy mounting thanks to very compact dimensions (only 9.2 mm thick).
• No separate power supply needed - the circuit draws power directly from the measured pack.
• Reliability - a wide operating temperature range allows trouble-free use in demanding conditions.