JBL Charge Essential 2 Replacement Battery GSP-1S3P-CH40 3.6V

JBL Charge Essential 2 — 3.6V Li-ion Replacement Battery (GSP-1S3P-CH40)

This is a 3.6V, 10000mAh Li-ion replacement battery for the JBL Charge Essential 2 Bluetooth speaker. It matches the OEM part number GSP-1S3P-CH40 and fits directly into the Charge Essential 2 housing. If your speaker no longer holds a charge or shuts down unexpectedly during playback, this battery restores normal function.

• Charge Essential 2 fit: The Charge Essential 2 uses a single 3.6V Li-ion pack in a 1S3P cell configuration. The battery communicates with the speaker's onboard BMS via a multi-pin connector. Voltage rail and connector pinout match the OEM spec — no firmware conflicts or protection tripping on power-up.
• Bench tested on actual hardware: We ran this pack on the Charge Essential 2 through full charge and discharge cycles. The BMS accepted the cell without fault codes, held the 3.6V nominal rail through high-volume playback, and the fuel gauge reported accurately from 100% down to the low-battery cutoff.
• Monthly discharge cycle for Charge Essential 2: The Charge Essential 2 is frequently left on a desk and topped off before it drops below 50%. Over time, the fuel gauge loses calibration and the speaker shuts off while showing bars remaining. Run it down below 20% at least once a month before recharging to keep the gauge accurate and slow capacity fade.

Audio distortion before the battery indicator reaches empty on Charge Essential 2

As the Li-ion cell discharges toward its lower voltage boundary, the available current drops. The Charge Essential 2 amplifier draws a spike of current at high volume levels. When the cell voltage sags under that combined amplifier and radio load, the amp clips before the protection circuit triggers a full shutdown. The result is crackling or compressed audio while the LED indicator still shows charge remaining. If distortion starts above 3.2V at the cell terminals, the pack has aged past usable capacity — a fresh cell at full charge holds the rail above 3.5V under the same load.

Charge Essential 2 won't wake from USB-C after sitting unused for weeks

A Li-ion cell left discharged for an extended period can drop below the USB-C Power Delivery minimum acceptance voltage — typically around 2.5V per cell. At that point the charger sees no handshake and delivers no current, so the speaker appears completely dead on any cable. To recover, use a charger that supports trickle or pre-charge mode and leave it connected for 20–30 minutes before expecting the LED to respond. If the cell has dropped below 2.0V it will not recover safely, and the pack should be replaced rather than force-charged.