About this replacement
JBL Charge 6 — 7.4V Li-ion Replacement Battery (GSP-2S10-CH6A)
This is a 7.4V, 4500mAh Li-ion replacement battery for the JBL Charge 6 portable Bluetooth speaker. It replaces OEM part GSP-2S10-CH6A and restores the speaker's wireless audio and USB charging output when the original cell has degraded or failed. Capacity figure is 33.3Wh at the rated 7.4V nominal.
- Charge 6 fit and connector: The Charge 6 uses a two-cell series Li-ion pack with a multi-pin connector that carries both cell balance data and temperature sensing. The BMS inside the speaker reads both signals on power-up — a pack missing either line will not initialise, so this replacement includes the matching harness and pin layout.
- Bench tested on actual hardware: We cycled this pack on a Charge 6 unit through charge, full audio playback load, and USB passthrough output. The BMS accepted the cell chemistry handshake on first power-up, and the protection circuit tripped correctly at the low-cell-voltage cutoff threshold without nuisance shutdowns during normal draw.
- Monthly discharge cycle for Charge 6 users: If the speaker sits on a desk and gets topped off before dropping below 50%, the fuel gauge drifts over weeks and the battery indicator becomes inaccurate. Run the speaker down below 20% at least once a month before recharging to recalibrate the gauge and slow capacity fade on the Li-ion cells.
Why the Charge 6 shows full charge but audio cuts out after extended play
The Charge 6 amplifier draws a spike of current each time bass transients hit at high volume. If the Li-ion cells have degraded, internal resistance rises and voltage sags sharply under that spike — even when the fuel gauge still reads high. The speaker's protection circuit sees the sag as a low-voltage condition and shuts audio output before the indicator reaches empty. Replacing the pack with fresh cells lowers internal resistance and eliminates the sag that triggers the premature cutoff.
USB-C won't wake the Charge 6 when the battery is deeply discharged
USB-C Power Delivery negotiation requires the device to pull a minimum voltage on the CC pins before the charger steps up to full charging voltage. If the Charge 6 battery has dropped below roughly 2.5V per cell, the BMS locks out output and the speaker cannot pull enough current to begin that handshake. The fix is to use a standard 5V USB-A cable first — this bypasses PD negotiation and trickle-charges the pack until cells recover above 3.0V per cell. Once the indicator LED blinks, switch back to the USB-C cable for normal charging.