About this replacement
Apple iPhone 7 Plus — 3.82V Li-Polymer Replacement Battery (616-00249)
This 3.82V, 2900mAh Li-Polymer cell replaces the internal battery in the iPhone 7 Plus. It fits models A1661, A1784, and A1785 — the full 2016 7 Plus lineup. Capacity matches the original Apple specification at 11.08Wh.
- A1661, A1784, A1785 fit: All three 7 Plus variants share the same battery bay dimensions, connector pinout, and BMS handshake protocol. The same cell covers every regional variant without modification.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on a 7 Plus board. The BMS negotiated correctly, charge termination triggered at full voltage, and the fuel gauge IC tracked the new cell's discharge curve without fault codes.
- Fuel gauge recalibration after swap: On first use after installation, disable fast charging and run one complete discharge-to-charge cycle at standard current. This lets the fuel gauge IC map its coulomb counter against the new cell's actual discharge curve before high-current charging begins.
Sudden shutdown at 20–30% after a cell swap
This happens because the fuel gauge IC is still calibrated to the old cell's voltage curve. The new cell hits a voltage cliff under modem or screen load that the gauge didn't predict. The phone reads 25% but the cell voltage has already dropped below the safe cutoff threshold. One full discharge-charge cycle without fast charging resets the coulomb counter and resolves this.
Phone warm near the battery during the first few charges
A fresh Li-Polymer cell has higher internal impedance than a broken-in cell. The charge IC pushes current into that resistance, generating heat at the battery. This is normal for the first two to three cycles and diminishes as the cell's impedance drops. If warmth persists past three full cycles, check that the connector is fully seated and the charge IC hasn't flagged a fault in the battery health menu under Settings → Battery.