EB555157VA AT&T Infuse 4G SGH-i997 Replacement Battery 3.7V 1850mAh

AT&T Samsung Infuse 4G SGH-i997 — 3.7V Li-ion Replacement Battery (EB555157VA)

This 3.7V 1850mAh Li-ion cell is a direct swap for the original EB555157VA battery in the Samsung Infuse 4G (SGH-i997). It fits the AT&T SGH-i997 smartphone and restores power capacity when the factory cell has aged out. Voltage and capacity match OEM spec at 3.7V and 1850mAh (6.85Wh).

• SGH-i997 fitment: The Infuse 4G uses a specific 56.00 x 50.20 x 5.20mm cell bay with a dedicated connector pinout tied to the phone's charge IC and fuel gauge loop. This cell matches those physical and electrical parameters so the BMS handshake completes on first boot.
• Bench tested on actual hardware: We ran this cell through a full charge and load cycle on the SGH-i997 platform. The BMS accepted the charge IC handshake without fault codes, and the fuel gauge IC registered capacity correctly after one complete cycle.
• First-cycle fuel gauge reset: After installation, disable fast charging and run one full discharge down to automatic shutdown, then charge uninterrupted to 100%. This gives the fuel gauge IC a clean reference curve to calibrate against the new cell before normal use.

Why the SGH-i997 reports wrong battery percentage after a cell swap

The Infuse 4G uses a coulomb counter in the fuel gauge IC that builds its percentage model from learned discharge curves of the old cell. When you install a new cell, the IC still references that stale curve. The result is percentage readings that lag reality — often showing 30–40% when the phone is close to cutoff voltage. One complete uninterrupted discharge-to-shutdown followed by a full charge resets the learning cycle. After that single calibration pass, percentage accuracy returns to normal.

Sudden shutdown at 20–30% on the replacement cell

This happens when the modem or display draws a current spike the fuel gauge IC did not anticipate from the new cell's discharge curve. The cell voltage dips below the BMS cutoff threshold — typically around 3.0V — under load, even though the reported percentage looks safe. The phone cuts out to protect the cell, not because the cell is faulty. Run the calibration cycle described above; once the fuel gauge IC has mapped the new cell's actual voltage-to-capacity curve, the premature shutdowns stop.