About this replacement
Trelock LS 950 — 3.7V Li-ion Replacement Battery (18650-22PM 2P1S)
This is a 3.7V, 4400mAh Li-ion replacement battery for the Trelock LS 950 front bicycle light. It fits both the LS 950 and LS950 variants. When the original cell degrades after repeated charge cycles, output brightness drops noticeably — this battery restores the light to full operating voltage.
- LS 950 compatibility: The LS 950 uses a 2P1S cell configuration — two 18650 cells in parallel, wired as a single series string. This battery matches that pack geometry, connector pinout, and the BMS communication the light driver expects for charge and discharge control.
- Bench tested on actual hardware: We cycled this battery through full charge and discharge on the LS 950 driver board. The BMS accepted charge from the light's USB input without fault flags, and the driver maintained stable output from full charge down to the low-voltage cutoff threshold.
- Pre-ride charging on the LS 950: Charge the light fully before a night ride. The LS 950 driver steps down output power progressively as cell voltage drops — a partially charged battery will run at reduced brightness well before the low-battery indicator activates.
Light not reaching rated lumen output after battery replacement
The LS 950 driver requires a minimum input voltage to sustain its highest brightness mode. If the replacement cell shipped at a low state of charge — common after storage — the driver may not have enough headroom to hit rated output. This is not a faulty battery. Run a full charge cycle first, then test brightness. The cell should sit at or above 4.1V after charging before you expect rated lumen output.
USB charging not accepted after riding in wet conditions
Moisture inside the LS 950's USB charging port interrupts the charge handshake between the charger and the battery BMS. The light will not draw current until the port is dry. Leave the port uncovered in a dry environment for several hours before attempting to charge again. Once dry, connect the charger and confirm the charge indicator activates — if it does not, inspect the port contacts for corrosion.