LG PH550 Portable Projector Replacement Battery 7.4V 3400mAh

LG PH550 — 7.4V Li-ion Replacement Battery (EAC63238201)

This 7.4V, 3400mAh lithium-ion battery replaces the original EAC63238201 cell in the LG PH550 portable projector. It restores cordless operation so the projector runs away from a wall outlet — for presentations, travel, or outdoor use. Voltage and capacity match the original specification exactly.

• PH550 platform fit: The PH550 uses a single-cell lithium-ion pack at 7.4V nominal. The BMS in this unit communicates directly with the projector's power management board, so voltage tolerance and cell chemistry both need to match — this pack meets both requirements.
• Bench tested on actual hardware: We ran this battery through charge and discharge cycles on the PH550 platform. The projector's BMS accepted the pack, cycled through charge states without fault codes, and lamp ignition held stable from full charge down through the low-battery warning threshold.
• Lamp draw management: Set the PH550 to eco brightness mode when running on battery. Full brightness pulls 30–40% more current from the pack than eco mode does. The difference in image quality is minimal in most indoor environments, but the current draw difference is significant.

Why the PH550 shuts off before the battery indicator reaches empty

The PH550's lamp requires a higher minimum supply voltage than the projector's low-battery cutoff threshold is calibrated for. As the cell discharges and internal resistance rises, voltage sags under lamp load — even when the gauge still shows charge remaining. The projector's power board detects the voltage drop and shuts the lamp down to protect the circuit. This is a design characteristic of the platform, not a fault with the battery.

PH550 shows "charging" but battery percentage never increases

This usually means the internal charger has lost communication with the pack's BMS, often because the cell voltage dropped below the charger's recovery threshold — typically around 2.5V per cell. The charger enters a trickle state, reports "charging," but never transitions to bulk charge. Remove the battery, leave it disconnected for 60 seconds, then reseat it firmly and reconnect the power adapter. If the percentage still does not move after 20 minutes, check that the adapter output is at the rated voltage before assuming the battery is at fault.