Shure GLXD+ Wireless Mic Compatible Battery 3.7V 3400mAh

Shure GLXD1+ / GLXD+ Series — 3.7V Li-ion Replacement Battery (95A43507 / SB904)

This 3.7V, 3400mAh (12.58Wh) lithium-ion cell replaces the internal rechargeable battery in Shure GLXD+ and GLXD1+ wireless transmitter body packs. It fits the standard transmitter housing used across the GLXD+ handheld and beltpack series. Swap it in when your original cell no longer holds enough charge to carry a full performance or session.

• GLXD+ and GLXD1+ transmitter fit: These transmitters share the same internal bay dimensions, connector pinout, and BMS handshake protocol — one cell covers the full GLXD+ generation without modification.
• Bench tested on actual hardware: We ran this cell in a GLXD1+ beltpack and confirmed the BMS accepted the charge cycle without fault flags, held voltage through simulated transmit load, and passed the battery status read-back to the receiver correctly.
• GLXD+ charging dock protocol: Always charge this cell in the Shure SBC840 or compatible GLXD charging dock — do not attempt charging through third-party USB adapters wired to the contacts. The GLXD BMS expects a dock-side handshake to initiate the charge curve; bypassing it can leave the cell partially charged or trigger a protection lock.

Voltage sag under sustained GLXD+ transmit draw

The GLXD+ transmitter runs a 2.4GHz OFDM RF chain that pulls short, sharp current spikes during transmission bursts. A degraded or low-capacity cell sags below the BMS cutoff threshold during these spikes before the battery indicator registers low. This triggers a momentary shutdown that reads as audio dropout at the receiver rather than a battery warning. A fresh 3400mAh cell at full charge maintains headroom above that cutoff threshold through the transmit peaks.

Receiver loses lock on transmitter immediately after battery swap

After installing a new cell, the transmitter must complete a full power cycle before it re-establishes the RF link with the paired receiver. If you pull the old battery with the unit active or reinsert without powering fully off, the transmitter may come back on a mismatched channel state. Power the transmitter fully off, insert the new cell, power back on, and confirm the receiver shows a locked link — check for a solid green RF indicator on the receiver front panel.