Samsung EB585157VK Galaxy S II HD LTE Replacement Battery 3.7V 1800mAh

Samsung Galaxy S II HD LTE / SHV-E120S — 3.7V Li-ion Replacement Battery (EB585157VK)

This is a 3.7V, 1800mAh Li-ion cell built to fit the Samsung SHV-E120S, Galaxy S II HD LTE (Celox), and SHV-E110S. It replaces OEM part EB585157VK and drops into the same battery bay with the same connector and BMS contact layout. Capacity figure is 1800mAh / 6.66Wh — use this, not third-party listings that inflate the spec.

• Galaxy S II HD LTE platform fit: The SHV-E120S, SHV-E110S, and Celox variants share the same PCB contact strip, connector polarity, and BMS handshake protocol. One cell covers all of them — no wiring or adapter needed.
• Bench tested on actual hardware: We cycled this cell on an SHV-E120S unit. The BMS accepted the handshake on first boot, charge IC registered a full 1800mAh draw on the first discharge, and no thermal flags were thrown during the initial charge-in cycle.
• Fuel gauge recalibration after swap: On first use, disable fast charging and run one complete discharge-to-charge cycle. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging pushes into an uncalibrated state — preventing erratic percentage readings from the first week onward.

Sudden shutdown at 20–30% on the SHV-E120S after a cell swap

This is a voltage cliff issue, not a capacity defect. When the modem or display pulls a high-current burst, a new cell that hasn't been calibrated can sag below the system's minimum voltage threshold — triggering an emergency shutdown even though the percentage counter still reads 20–30%. The fuel gauge IC on the SHV-E120S uses a coulomb counter that was calibrated to the old, degraded cell curve. Run one full uninterrupted discharge until the phone shuts off naturally, then charge to 100% without interruption to reset the reference points.

Phone won't power on after the replacement battery sat in storage

Li-ion cells shipped in storage state typically sit at 3.6–3.8V — enough for normal boot. If the cell dropped below 2.5V during extended warehouse storage, the BMS enters lockout mode and blocks charge current entirely to prevent cell damage. The phone will show nothing: no boot screen, no charge indicator. Connect to a wall adapter — not a PC port — and leave it for 15–20 minutes before attempting to power on. A USB wall adapter delivering at least 5V/1A is enough to nudge the BMS out of lockout and begin trickle charge recovery.