EB575152VU Sprint Epic 4G Replacement Battery 3.7V 1550mAh

Sprint Epic 4G — 3.7V Li-ion Replacement Battery (EB575152VU)

This is a 3.7V, 1550mAh Li-ion replacement battery for the Sprint Samsung Epic 4G Android smartphone. It fits the original battery slot and replaces OEM part numbers EB575152VU, EB575152VA, EB575152LU, and EB575152LA. Capacity is rated at 5.74Wh, matching the original cell specification.

• Epic 4G compatibility: The Epic 4G uses a single-cell 3.7V Li-ion pack with a three-contact connector carrying positive, negative, and thermistor lines. This battery matches that connector pinout and communicates correctly with the phone's charge IC over the thermistor line, so the device accepts charging without throwing a temperature fault.
• Bench tested on actual hardware: We ran this cell through charge and discharge on the Epic 4G platform. The BMS held cutoff correctly at the low-voltage threshold and did not trigger a premature shutdown during high-draw screen-on cycles. The charge IC accepted the cell and reached termination current without errors.
• Fuel gauge recalibration on first use: Disable fast charging for the first complete discharge-charge cycle after installation. This gives the fuel gauge IC one full sweep of the new cell's discharge curve before high-current charging begins. Skipping this step is the most common reason the percentage readout jumps or reads incorrectly in the first few days.

Sudden shutdown at 20–30% on the replacement cell

The Epic 4G's fuel gauge IC stores a discharge curve from the previous cell. When a new cell goes in, the stored curve no longer reflects the actual voltage-to-capacity relationship of the replacement. Under modem load or screen-on draw, the cell voltage dips faster than the IC expects, and the phone interprets this as a critically low voltage and cuts power. This is not a defective battery — it is a calibration gap. One full discharge to shutdown followed by an uninterrupted charge to 100% resets the coulomb counter and eliminates most cliff-shutdowns.

Phone warm near the battery compartment during first charge

A new Li-ion cell has higher internal impedance than a cell that has been cycled. On the first charge, the charge IC pushes current into this higher-resistance cell, and the extra energy dissipates as heat at the cell surface. This is normal and typically resolves after two or three full cycles as impedance drops. If the phone stays warm past the third cycle, check that the back cover is fully seated — a partially open cover traps heat against the battery. If warmth persists beyond cycle three, measure the charge termination: the IC should drop to trickle current before the phone reads 100%.