JBL Flip Essential 2 Replacement Battery 3.7V 2600mAh

JBL Flip Essential 2 — 3.7V Li-ion Replacement Battery (ICA085NA)

This is a 3.7V, 2600mAh Li-ion replacement battery for the JBL Flip Essential 2 portable Bluetooth speaker (JBLFLIPES2). It slots into the same position as the original ICA085NA cell and restores wireless audio and hands-free calling functionality. Use the capacity figure from this listing — 2600mAh — as your reference.

• Flip Essential 2 fit note: The JBLFLIPES2 uses a slim 71 × 20 × 20mm cell with a specific connector orientation tied to the board's fuel gauge IC. This replacement matches that geometry and connector pin-out so the BMS handshake completes on first power-up.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the Flip Essential 2 board. The BMS accepted the cell without error flags, charge termination triggered correctly at 4.2V, and protection cutoff activated at the expected low-voltage threshold.
• Fuel gauge reset after install: After fitting, run the speaker down until it powers off on its own, then charge it uninterrupted to 100%. This forces the fuel gauge IC to re-calibrate its empty and full reference points against the new cell — skipping this step leaves the indicator reading inaccurately from day one.

Audio distorting before the battery indicator reaches empty

As a Li-ion cell ages, its internal resistance rises. Under the combined current draw of the amplifier and Bluetooth radio, voltage sags below what the amp needs before the fuel gauge registers low. The amplifier clips — producing distortion — while the display still shows charge remaining. A fresh cell with lower internal resistance maintains voltage under that combined load, so the amp stays in its clean operating window until the cell is genuinely depleted.

Bluetooth dropping specifically at high volume on the Flip Essential 2

At high volume, the amplifier pulls a sharp current spike on top of the Bluetooth radio's steady draw. A degraded or deeply cycled cell cannot deliver that combined current without the voltage rail momentarily collapsing. When it drops below the radio module's minimum operating voltage, the Bluetooth stack resets and the connection drops. Fitting a new cell restores the headroom needed — if drops persist on a new cell, check that the USB-C charge port is clean and the cell is sitting above 3.8V at rest before blaming the radio module.