JBL Clip 4 Compatible Battery GSP903052 3.7V 1100mAh

JBL Clip 4 — 3.7V Li-Polymer Replacement Battery (GSP903052)

This 3.7V, 1100mAh Li-Polymer cell replaces the original GSP903052 battery in the JBL Clip 4 portable Bluetooth speaker. It fits the Clip 4 and AN0402-JK0009880 variants. Dimensions are 49.50 × 30.00 × 8.50mm — measure your original before installing.

• Clip 4 and AN0402-JK0009880 compatibility: Both models run the same single-cell Li-Polymer configuration at 3.7V nominal, use the same flex-ribbon connector footprint, and communicate with the same fuel gauge IC — so one cell covers both variants without modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a Clip 4 unit. The onboard BMS accepted charge immediately, balanced correctly at 4.2V, and the protection circuit tripped cleanly at the low-voltage cutoff without hanging the firmware.
• Monthly discharge cycle for the Clip 4: The Clip 4 spends most of its life clipped to a bag or desk, constantly topped off. Let the speaker discharge below 20% at least once a month before recharging — constant partial charging without a full discharge cycle causes fuel gauge drift and accelerates capacity fade on the cell.

Bluetooth dropping at high volume on the Clip 4

At maximum volume, the Clip 4 amplifier and Bluetooth radio draw current simultaneously. On a degraded or low-state-of-charge cell, this combined load causes voltage sag past the radio's operating floor — the Bluetooth stack drops to protect itself. The fix is straightforward: a fresh cell with lower internal resistance holds the voltage rail steady under combined amp and radio load. If dropout persists on a new battery, check that the USB-C port is clean and the charger is delivering at least 5V 1A to ensure the cell is reaching a full 4.2V before use.

Audio distorting before the battery indicator reaches empty

The amplifier inside the Clip 4 clips its output signal when the supply voltage sags — this produces audible distortion at moderate-to-loud volume levels well before the indicator shows low battery. The root cause is elevated internal resistance in an aged cell: the resting voltage reads normal, but voltage collapses under load. Replacing the cell restores a flat discharge curve. After fitting this battery, confirm the speaker reaches 4.2V at end of charge with a multimeter probe on the charging contacts before reassembly.