About this replacement
JBL TAS8528P / BAR 800 Series — 3.7V Li-ion Replacement Battery (ICA039NA)
This is a 3.7V 2600mAh (9.62Wh) Li-ion cell for the JBL TAS8528P, TAS8528M, and BAR 800 5.1.2-channel soundbar. It replaces part numbers ICA039NA and DH036032CHM. Fit this battery when your original cell no longer holds a charge or has swollen inside the housing.
- TAS8528P, TAS8528M, and BAR 800 compatibility: These models share the same 3.7V single-cell architecture, connector pinout, and BMS handshake protocol — one cell fits all three without any modification to the wiring harness.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the TAS8528P platform. The onboard BMS accepted the cell, completed a full charge cycle without fault flags, and held stable voltage under combined amplifier and Bluetooth radio draw.
- Fuel gauge calibration for daily-use speakers: Let the speaker discharge below 20% at least once a month before plugging it in. Constant top-off charging without a full discharge causes fuel gauge drift — the indicator reads full while the usable capacity has quietly dropped.
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 at high volume, terminal voltage sags faster than the fuel gauge tracks it. The amplifier clips before the cell is technically empty, so you hear distortion with the indicator still showing 20–30%. Replacing the cell drops internal resistance back to spec — distortion at high volume disappears when resting cell voltage holds above 3.6V under load.
Speaker won't wake from USB-C after sitting unused for weeks
A deeply discharged Li-ion cell can drop below the USB-C PD minimum acceptance voltage — typically around 2.5V — and the charger controller refuses to initiate a charge session. The BMS sees the cell as outside its safe recovery window and blocks current. To recover, use a 5V/0.5A USB-A-to-C cable rather than a PD charger; lower-current trickle input can bring the cell back above the acceptance threshold. Once the indicator light activates, switch to your normal charger and complete a full cycle.