About this replacement
LG XBOOM Go XG9 — 14.8V Li-ion Replacement Battery (EAC64790801)
This is a 14.8V, 5200mAh Li-ion replacement battery for the LG XBOOM Go XG9 portable Bluetooth speaker. It fits XG9QBK variants including ABRALLB, ABRALLK, and DEUSLLB. Swap it when the original pack no longer holds enough charge to get you through a full session away from mains power.
- XG9 variant compatibility: All listed XG9QBK variants share the same 14.8V battery bay, connector pinout, and BMS communication protocol. The cell count and voltage rail are identical across the regional SKUs, so one pack covers the full XG9 family.
- Bench tested on actual hardware: We cycled this pack through charge and discharge on the XG9 platform and confirmed the BMS handshake completed without fault codes. Cell balancing across the four Li-ion cells settled within spec after the second full cycle.
- Monthly discharge for fuel gauge accuracy: If the XG9 lives on a desk and gets topped off constantly, discharge it below 20% at least once a month before recharging. Constant shallow cycling causes the fuel gauge IC to drift, so the speaker reports full charge while actual usable capacity quietly drops.
Audio distortion before the battery indicator reaches empty on the XG9
The XG9 amplifier draws a sharp current spike when reproducing bass-heavy content at high volume. As the Li-ion pack ages and internal resistance climbs, voltage sags under that spike before the fuel gauge registers low battery. The amplifier clips the output signal to protect itself, and you hear distortion well before the indicator flashes empty. A fresh pack with lower internal resistance eliminates the sag — at 14.8V nominal, the amplifier stays above its minimum rail voltage even under peak draw.
USB-C charging not starting on a deeply discharged XG9 pack
If the XG9 has sat unused for weeks, the cell voltage can drop below the USB-C Power Delivery minimum acceptance threshold, and the charger will not negotiate a session — the indicator stays dark and nothing happens. The BMS needs a trickle pre-charge to bring the cells back above roughly 2.5V per cell before it will allow a standard charge cycle. Connect the speaker to a USB-C charger rated at least 18W and leave it untouched for 20–30 minutes — the BMS will begin pre-charge recovery on its own without any reset step required.