Fly TS110 Compatible Battery BL6703 3.7V 2000mAh Li-ion

Fly TS110 — 3.7V Li-ion Replacement Battery (BL6703)

This is a 3.7V, 2000mAh Li-ion replacement battery for the Fly TS110 smartphone. It fits directly in place of the original BL6703 cell. Use it to restore a phone that no longer holds charge or shuts down unexpectedly under load.

• TS110 platform fit: The TS110 uses a single-cell Li-ion pack at 3.7V nominal. The BL6703 form factor — 68.20 × 43.95 × 6.40mm — matches the battery bay exactly, and the connector orientation lines up with the board's charge IC input rail without modification.
• Bench tested on actual hardware: We ran this cell through full charge and discharge cycles on the TS110 platform. The BMS accepted charge current correctly, protection circuitry tripped cleanly at the low-voltage cutoff threshold, and the charge IC reported cell status without fault codes.
• Fuel gauge recalibration on first use: After installation, disable any fast-charge mode for the first complete discharge-to-charge cycle. This allows the fuel gauge IC to map the new cell's discharge curve before high-current charging is applied to an uncalibrated cell — preventing erratic percentage readings from the start.

Sudden shutdown at 20–30% on the TS110 after a cell swap

The TS110's fuel gauge IC stores a discharge model calibrated to the old cell. When a new cell is installed, that model no longer matches the actual voltage curve. At around 20–30% reported charge, the new cell's voltage drops below what the modem and display draw can sustain — the phone cuts out even though the gauge shows charge remaining. One full slow-charge cycle after the swap lets the coulomb counter reset its reference points against the new cell. After that cycle, the gauge tracks accurately and the shutdowns stop.

Phone warm near the battery compartment on first charge after replacement

A new high-impedance cell generates more heat during the first few charge cycles than a conditioned cell does. The charge IC on the TS110 applies a constant current phase that the fresh cell resists at higher internal resistance, converting some energy to heat. This is normal and tapers off after two to three full cycles as internal resistance drops. If the device stays warm beyond the third charge cycle, check that the battery cover is seated flat — a lifted cover traps heat and can mask a contact seating issue at the connector.