Monster AVL300s Remote Control Replacement Battery 3.7V 950mAh

Monster AVL300s / MCC-AV100 — 3.7V Li-ion Replacement Battery

This is a 3.7V, 950mAh Li-ion replacement battery for the Monster AVL300s, AVL300, and MCC-AV100 wireless remote controls. These remotes handle volume control, input selection, and playback functions for Monster home entertainment systems. When the original cell depletes, this direct swap restores full IR output.

• AVL300s, AVL300, and MCC-AV100 compatibility: All three remotes share the same single-cell 3.7V Li-ion architecture and connector footprint. The cell dimensions — 53.07 x 33.08 x 7.78mm — match the original battery bay without modification.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge on the bench. The BMS maintained stable voltage across IR LED firing, with no undervoltage cutoff under normal remote-use load.
• Single-cell Li-ion handling: Do not expose this remote to direct heat sources like sunlight on a glass shelf or near an AV receiver vent — Li-ion cells in compact remotes have minimal thermal mass and degrade faster above 40°C than alkaline alternatives would.

Why the AVL300s stops responding immediately after a new battery install

The most common cause is reversed polarity. The AVL300s battery bay is compact and the positive terminal markings can be easy to miss under poor lighting. A backwards cell delivers no voltage to the IR LED driver circuit, so the remote appears completely dead. Check the embossed + and − symbols inside the bay against the battery terminals before assuming the replacement cell is faulty. Correct orientation restores function immediately — no reset required.

AVL300s remote range shrinking — needs to point directly at the device

When the battery voltage drops below roughly 3.4V, the IR LED doesn't fire at full intensity. The remote still sends a signal, but only at close range and with a narrow angle. This is a gradual fade, not a sudden cutoff, so it can look like an IR sensor problem on the receiver end. If the remote only works within half a metre or needs to be aimed precisely, the cell is near end of life — replace it before it drops further and stops triggering the receiver at any distance.