About this replacement
Shure GLXD1 / GLXD2 GLX-D Digital Wireless — 3.7V Li-ion Replacement Battery (SB902 / SB902A)
This is a 3.7V, 1100mAh Li-ion cell that fits the Shure GLXD1, GLXD2, GLX-D Digital Wireless systems, and MXW2 bodypack transmitters. All of these units share the same battery bay dimensions and SB902/SB902A form factor. Capacity is 4.07Wh — identical to the original Shure spec.
- GLXD1, GLXD2, and MXW2 compatibility: These models share the same 3.7V single-cell architecture, identical connector pinout, and the same BMS handshake protocol. One battery fits all four units without modification.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a GLXD2 unit. The BMS accepted the cell cleanly, reported correct charge state on the transmitter's LED indicator, and held voltage within spec through the full discharge curve.
- Transmitter duty-cycle care: The GLXD series uses 2.4GHz DECT transmission, which draws burst current during frequency-hopping handshakes. Avoid storing the transmitter with the battery partially charged for weeks at a time — burst-draw on a half-depleted cell accelerates internal resistance buildup faster than on a fully rested cell.
Why the GLXD1 drops signal mid-performance even with bars showing on the transmitter
The GLXD1's fuel gauge reads state-of-charge from a voltage model, not a coulomb counter. As internal resistance climbs in an ageing cell, voltage sags sharply during the transmitter's RF burst — enough to trip the under-voltage cutoff — while the resting voltage still looks healthy to the gauge. The transmitter interprets this as a dropout rather than a low-battery event, so the indicator stays green. Replacing the cell resets the internal resistance to spec and eliminates the sag-induced cutoffs.
GLXD transmitter not recognised by the SBC-GLXD charger dock after a long storage period
If the SB902 cell sits dormant for several months, voltage can fall below 3.0V — the threshold at which the SBC-GLXD charger's wake circuit stops attempting a charge cycle. The dock sees the cell as a fault condition rather than a discharged pack and shows no charge activity. To recover, use a lab charger or a USB charger capable of pre-charge mode to raise the cell above 3.1V, then reinsert into the dock. Once above that threshold, the dock resumes normal CC/CV charging without issue.