503759-2S 7.4V 1200mAh Rechargeable Battery Pack

The Ufine 503759-2S is a 7.4V 1200mAh rechargeable LiPo battery pack with 8.88Wh of nominal energy. It uses a 2S1P layout and includes a protection board. Its maximum body size is 10 × 37 × 62mm.

For this pack, a useful design review starts with one full device task. Check the power needed to start, run, and finish that task. Then review charging, installation, and storage.

Can the 503759-2S complete your device duty cycle?

A device may spend most of its time asleep, then draw more power to take a reading, send data, or turn on a light. Measure each mode to build a useful power estimate.

• For a data logger, measure sleep time and power used for each reading.

• For a wireless instrument, include the time needed to connect and send data.

• For an LED light, check each brightness setting.

• For all devices, record startup current and how long the peak lasts.

The listed maximum discharge current is 1200mA. A low average current does not mean every peak is within this limit. Share the measured load if your device has brief bursts of high demand.

Estimate runtime from the battery side of the circuit

Use battery-side current when making a simple capacity-based estimate. Current measured after a voltage converter may give a different result.

Ideal runtime (hours) ≈ 1200mAh ÷ average battery current (mA)

• At 120mA average battery current: about 10 hours in theory.

• At 240mA average battery current: about 5 hours in theory.

• At 600mA average battery current: about 2 hours in theory.

These estimates assume the full rated capacity is available. Actual runtime depends on temperature, battery age, load, and the device shutdown voltage. Confirm the result in the finished product.

Check what happens as the pack voltage falls

The 7.4V rating is nominal. The pack reaches 8.4V at full charge, then its voltage falls during use. Your device must work across the planned battery voltage range.

• Check that the device input can accept 8.4V at full charge.

• Test display, light, and wireless functions near the end of a charge.

• Check voltage drop during the highest load.

• Set a device shutdown point that follows the approved pack specification.

The listed discharge cut-off is 5.5V. Review this value when setting the device power controls. Avoid relying on the protection board to end every normal use cycle.

Define the charging connection before choosing the plug

The 503759-2S needs a compatible 2S lithium-ion CC/CV charger with an 8.4V charge limit. The detailed specification lists a standard charge current of 240mA and a maximum of 1200mA.

• Confirm whether charging takes place inside the device or in a separate charger.

• Match the connector pin layout and polarity to the approved drawing.

• Review any cell monitoring or balancing needs. PCM inclusion alone does not confirm balancing.

• The standard pack has no NTC. Confirm whether the charger needs a temperature sensor.

Charge only within the listed 0°C to 45°C range. Check pack temperature with the device housing closed, especially when the device runs while charging.

Plan for time on the shelf as well as time in use

Some products spend weeks in storage before the next charge. A device can still draw power while its screen is off. Measure this drain with the battery connected.

• Check standby current and any power used by timers or wireless functions.

• Confirm whether the power switch fully disconnects the load.

• Set a battery check schedule for stored devices.

• Keep connectors protected from short circuits during storage and handling.

The listed storage temperature ranges are −20°C to 30°C for one year, −20°C to 45°C for three months, and −20°C to 60°C for one month. These are temperature limits for each period. They do not promise a full charge after storage.

Use the sample to settle the final assembly details

A sample should match the planned wire route and connector. Test it in the real housing so you can find fit and connection issues before ordering production packs.

• Check the 10 × 37 × 62mm maximum body size against the available space.

• Allow separate room for the leads, connector, and assembly clearance.

• Make sure the housing closes without pressing on the pack or trapping wires.

• Record the sample version and the results of device testing.

MSDS is listed for this model. Tell us which other reports or shipping documents your project needs so their availability can be checked before the order.

Send your device load, battery space, charging details, and sample quantity. Include a connector photo or drawing if the pack must match an existing socket.