Cricket Source 3.8V Replacement Battery 2000mAh Li-ion

Cricket Source / N9511 — 3.8V Li-ion Replacement Battery

This is a 3.8V, 2000mAh Li-ion battery for the Cricket Source (model N9511). It fits directly into the phone once the original cell is removed. Use this when the existing battery no longer holds a charge or the phone shuts down unexpectedly under load.

• Source / N9511 fit: Both model names refer to the same hardware platform. The phone uses a 3.8V nominal cell with a standard Li-ion BMS handshake — this battery meets that spec without any modification.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the bench. The BMS accepted charge from the device's onboard charge IC without triggering a protection cutoff, and voltage output stayed stable under simulated screen and modem load.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging and run one complete discharge-charge cycle before relying on the percentage readout. The fuel gauge IC is calibrated to the old cell's discharge curve — one full cycle lets it map the new cell accurately before fast-charge current is introduced.

Sudden shutdown at 20–30% on the replacement cell

This is a voltage-cliff failure. Under modem or display load, the cell's actual voltage drops below the BMS cutoff threshold before the fuel gauge reads zero. The gauge still shows 20–30% because its coulomb counter was calibrated to a different discharge curve. One full discharge-charge cycle resets the coulomb counter against the real capacity of the new cell. After that cycle, the percentage readout tracks actual voltage correctly.

Phone feels warm near the battery during the first few charges

A new cell arrives with higher internal impedance than a well-cycled battery. During the first two or three charges, the charge IC pushes current into a cell that hasn't settled — that converts more energy to heat than usual. This is not a fault. Impedance drops as the cell cycles. If warmth persists past the third full charge or the phone gets hot enough to be uncomfortable, stop charging and check for a swollen cell.