About this replacement
LG PH450U / PH450UG — 7.4V Li-ion Replacement Battery (EAC63379202)
This is a 7.4V, 3000mAh Li-ion battery for the LG PH450U and PH450UG portable projectors. It slots into the same battery bay as the original EAC63379202 cell and restores untethered operation. Use this when the original pack no longer holds a charge or the projector shuts off earlier than it used to.
- PH450U and PH450UG compatibility: Both models run the same 7.4V battery rail with the same connector and BMS handshake protocol. One cell covers both variants — no wiring or adapter differences between them.
- Bench tested on actual hardware: We cycled this pack on a PH450U and confirmed the BMS accepted the cell, reported charge state correctly, and held stable voltage through full discharge to the projector's cutoff threshold.
- Eco mode draw on battery: Set the projector to eco brightness before unplugging from mains. Full lamp brightness pulls 30–40% more current than eco mode. The lamp requires a higher minimum voltage than the fuel gauge empty indicator — the projector will shut off before the battery reads flat if the draw is too high.
Why the PH450U cuts out before the battery indicator reaches empty
The PH450U's lamp has a higher minimum operating voltage than the BMS low-voltage cutoff. At full brightness, current draw pulls the cell voltage below the lamp's floor before the battery gauge reads zero. The projector interprets this as a hard fault and kills the lamp to protect the cell. Running eco mode keeps current draw low enough that the lamp stays above its minimum voltage all the way to actual battery cutoff — around 6.0V under load.
Projector not detecting a new battery after swap
If the PH450U shows no battery icon or refuses to start on the new cell, the BMS may need a recognition cycle. Plug the projector into mains with the new battery installed and let it charge uninterrupted until the charge indicator goes solid. This completes the initial BMS handshake. If the projector still doesn't register the pack, check that the battery contacts are fully seated — the bay latch must click closed before the BMS can communicate with the cell.