About this replacement
Vancouver XC-141K — 3.7V Li-Polymer Replacement Battery (14-11-28)
This 3.7V, 1500mAh Li-Polymer cell replaces the original battery in the Vancouver XC-141K bicycle light. It matches the OEM part number 14-11-28 and fits the compact cavity of the XC-141K housing. Voltage and capacity figures are taken directly from the product specification — 5.55Wh total energy.
- XC-141K light driver compatibility: The XC-141K uses a constant-current LED driver tuned to a 3.7V Li-Polymer input rail. Swapping to a different chemistry or nominal voltage causes the driver to pull incorrect current, which reduces output or triggers early cutoff. This cell keeps the driver inside its rated input window.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the XC-141K platform. The BMS accepted charge without interruption, and the driver maintained stable output from full charge down to the low-voltage cutoff threshold — no false low-battery trips during testing.
- Pre-ride charge check: Charge the XC-141K fully before a night ride. The LED driver steps down output power as cell voltage decreases, so a partially charged cell will run at reduced brightness well before the low-battery indicator activates.
Light dimming before the low-battery indicator appears
The XC-141K driver uses a voltage-based step-down curve, not a flat regulation stage. As the cell drops below roughly 3.5V under load, the driver reduces current to the LED to protect the cell from over-discharge. This happens before the low-battery indicator threshold is crossed in firmware. The result is visible dimming that riders often misread as a faulty battery. Starting a ride at full charge — 4.2V — keeps the driver in its full-output range for the entire usable capacity.
USB charging not accepted after a wet ride
Water in the USB port causes the XC-141K to reject charge input — the port's contact resistance rises enough that the charger handshake fails. This is not a battery fault. Allow the port to dry completely, standing the light upright with the port facing down, before attempting to charge again. Once dry, plug in and confirm the charge indicator LED activates within 10 seconds.