Customer:
I have questions regarding the specification of the Li-Ion battery 680 mAh 48 x 30 x 4 mm. The spec sheet appears to be missing from the documentation. Can you provide information on: 1. What ranges of voltages and currents are protected in the over-/undercharging protection? 2. Does the battery protect against thermal abnormalities? 3. Do you have info about the charging graph for prediction of charge percentage?
Originally submitted via email support on 6 April 2026. Migrated to the forum for community visibility.
Soldered Support:
The built-in Protection Circuit Module (PCM) stops the charging process if any cell reaches an overcharge limit of 4.25V (± 0.025V). To prevent over-discharging, the PCM will cut off the load when the battery voltage drops to 2.5V (± 0.1V). The standard maximum charge and discharge current is 1C, equating to 600mA for your battery, while the PCM safeguards against external short circuits by cutting off excessive current flow.
The battery does not feature built-in active thermal protection, such as an NTC thermistor, to automatically shut down based on temperature. The integrated circuitry only monitors voltage and current limits to prevent electrical damage. You must ensure the battery stays within its safe operating temperatures of 0°C to 45°C during charging and -10°C to 60°C during discharging.
Estimating the exact State of Charge (SoC) purely from a voltage graph is difficult because Li-ion batteries exhibit a very flat discharge curve around their 3.7V nominal voltage. While 4.2V generally indicates a full charge and 2.5V represents a fully depleted battery, the voltage changes minimally throughout the middle of the cycle. We recommend experimenting by plotting a discharging graph and then mapping a function to get the percentages. It’s often a case-by-case thing from our experience.
Attachment omitted in migration: Soldered_MSDS.pdf
Attachment omitted in migration: Soldered_500-mAh_datasheet.pdf
Customer:
The datasheet I received suggests both a 0.2C and a 0.5C charge current for the CC phase. I want to confirm: am I safe to use the higher 0.5C charge current, since it is still well below the max 1C charging current?
Attachment omitted in migration: rC1R3R6o0ifzZUgn.png
Soldered Support:
Yes, you can use 0.5C safely - it’s well within the 1C limit.