About this replacement
LG D320 / MS323 Series — 3.8V Li-ion Replacement Battery (BL-52UH)
This is a 3.8V, 1800mAh Li-ion replacement battery for the LG D320, MS323, D325, D329, and over 27 additional LG smartphone models sharing the BL-52UH platform. It replaces OEM part numbers BL-52UH, EAC62258202, and BL-52UHB. Swap it in when the original cell no longer holds a usable charge or shuts the phone down unexpectedly at partial capacity.
- BL-52UH platform compatibility: The D320, MS323, D325, and D329 all share the same connector pinout, BMS handshake protocol, and 3.8V nominal voltage rail — that's why one cell covers all of them without modification or adapter wiring.
- Bench tested on actual hardware: We ran this cell through full charge and discharge cycles on LG D320 hardware. The BMS negotiated correctly with the charge IC, accepted current without tripping into protection mode, and reported state-of-charge to the fuel gauge IC without error flags.
- Fuel gauge recalibration on first install: After installing this cell, disable fast charging and run one complete discharge-to-charge cycle before normal use. The fuel gauge IC is still calibrated to the old cell's discharge curve — one full cycle lets it map the new cell's voltage profile before high-current charging begins.
Sudden shutdown at 20–30% on the LG D320 after a cell swap
This happens because the fuel gauge IC was calibrated to the original cell's voltage curve, not the new one. When the phone draws a burst of current — modem transmission, screen wake, or a background sync — the new cell's voltage drops momentarily below the shutdown threshold even though the displayed percentage looks safe. The phone interprets that voltage sag as a critically low cell and cuts power immediately. Run one full discharge cycle from 100% down to automatic shutdown, then charge to 100% uninterrupted — after that cycle, the fuel gauge IC recalibrates its coulomb counter against the new cell and the false shutdowns stop.
Phone not powering on after the replacement battery sat in storage
Li-ion cells self-discharge in storage, and if the BL-52UH cell dropped below approximately 2.5V per cell, the BMS enters lockout mode to prevent damage from deep discharge. The phone won't respond to the power button and may show no charge indicator at all. Connect the phone to a wall charger — not a USB port — and leave it undisturbed for 15–20 minutes. The charge IC will trickle current into the cell at a low rate until voltage rises above the BMS re-enable threshold, typically around 3.0V, at which point normal charging resumes and the phone will power on.