Cricket EC1002 HE399 Replacement Battery 3.85V 3100mAh

Cricket EC1002 / Ovation 2 — 3.85V Li-Polymer Replacement Battery (HE399)

This is a 3.85V, 3100mAh Li-Polymer replacement battery for the Cricket EC1002 and Ovation 2 smartphones. It replaces OEM part number HE399. Swap it when the original cell no longer holds a charge or swells enough to lift the back cover.

• EC1002 and Ovation 2 fitment: Both devices share the same battery bay dimensions (85 × 63 × 4mm), the same 3.85V nominal voltage rail, and the same HE399 connector and BMS handshake — one cell covers both models.
• Bench tested on actual hardware: We ran this cell through charge-discharge cycles on the EC1002 platform. The BMS accepted the USB charge handshake without fault codes, and the protection circuit tripped correctly at the low-voltage cutoff threshold during deep-discharge stress testing.
• Fuel gauge recalibration on first install: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging pushes current into an uncalibrated cell — preventing erratic percentage readings from the first day.

Sudden shutdown at 20–30% on the EC1002 after a cell swap

This happens when the fuel gauge IC is still calibrated to the old cell's discharge curve. The chip reads 25% state-of-charge, but the new cell's actual voltage under modem or display load drops below the system shutdown threshold before the gauge catches up. The fix is one full discharge-charge cycle with fast charging disabled — this forces the coulomb counter to re-anchor against the new cell's actual capacity. After that cycle, the gauge tracks correctly and the early shutdowns stop.

Phone warm near the battery during the first few charges after replacement

A new high-impedance Li-Polymer cell converts more energy to heat early in its life because its internal resistance is slightly higher than a broken-in cell. The charge IC compensates by adjusting current, but that process generates warmth at the battery contact area for the first two or three full cycles. This is normal and not a sign of a fault — surface temperature should stay below 40°C. If the phone feels hot rather than warm, or if it is hot on the back near the top edge where the charge IC sits, stop charging and check the USB cable and adapter output voltage with a USB meter.