Kazuna eTalk MYFLIX BP1736 Replacement Battery 3.8V 1800mAh

Kazuna eTalk MYFLIX / KAZN20 — 3.8V Li-ion Replacement Battery (BP1736)

This is a 3.8V, 1800mAh Li-ion replacement for the Kazuna eTalk MYFLIX and KAZN20 smartphones. It fits the BP1736 OEM slot directly and restores power to the device. Dimensions are 68.10 × 58.00 × 4.50mm — confirm clearance before ordering.

• eTalk MYFLIX / KAZN20 / KAZN20PP fit: All three models share the same battery bay geometry, connector pinout, and BMS communication protocol. One cell covers all three variants — no wiring differences between them.
• Bench tested on actual hardware: We ran this cell through full charge and discharge cycles on the KAZN20 platform. The BMS handshake completed on the first cycle, charge current stepped down correctly at 4.2V, and protection cutoff triggered normally at low-voltage threshold.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC build a new discharge curve against the replacement cell before high-current charging is applied to an uncalibrated state.

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

The eTalk MYFLIX uses a coulomb-counter fuel gauge IC that was calibrated to the original cell's discharge curve. When a new cell goes in, the IC still references the old curve, so its voltage-to-percentage mapping is off. Under modem or screen load, the actual cell voltage drops below the shutdown threshold before the reported percentage reaches zero. The phone cuts out even though the display shows charge remaining. One full discharge-to-shutdown followed by an uninterrupted charge to 100% resets the calibration against the new cell.

Phone feels warm near the battery compartment on the first few charges

A new Li-ion cell has slightly higher internal impedance than a broken-in cell. The charge IC pushes the same current into higher resistance, which generates more heat at the cell surface during the first several cycles. This is normal and reduces as impedance drops with cycling. If warmth persists past the third full charge or the case becomes hot to the touch, stop charging and check that the battery is seated flat with no pressure on the connector pins.