K-Touch T789 Replacement Battery 3.7V 1300mAh TBW5932

K-Touch T789 / C980 Series — 3.7V Li-ion Replacement Battery (TBW5932)

This is a 3.7V, 1300mAh Li-ion replacement battery for the K-Touch T789, C980, C980T, and C988T smartphones. It replaces OEM part number TBW5932 and fits directly into the battery bay on these models. The cell measures 60.60 × 50.11 × 4.42mm — verify your original against those dimensions before ordering.

• T789, C980, C980T, C988T shared platform: These models run the same battery bay geometry and connector pinout. The BMS handshake voltage and thermistor pin placement are identical across the group, so one replacement cell covers all four variants without modification.
• Bench tested on actual hardware: We cycled the cell through charge and full discharge on a C980T. The BMS accepted charge current cleanly, held the low-voltage cutoff at the expected threshold, and did not trip the protection circuit under normal screen-on load.
• Fuel gauge recalibration on first cycle: After fitting this cell, disable fast charging and run one complete discharge-charge cycle at standard current. This lets the fuel gauge IC map its coulomb counter to the new cell's discharge curve before fast charge pushes higher current into an uncalibrated cell.

Sudden shutdown at 20–30% on the K-Touch C980 and T789

This happens when the cell cannot sustain voltage under peak modem or display load — even though the fuel gauge still reads a comfortable percentage. The voltage collapses faster than the coulomb counter can report, so the phone shuts down before the reading reaches zero. It is most common when the fuel gauge IC has not yet recalibrated to the new cell's discharge curve. Run one full discharge-charge cycle without fast charging and the reading will stabilise.

Phone warm near the battery bay on the first few charges

A freshly manufactured Li-ion cell has slightly higher internal impedance than a cell that has been cycled. The charge IC works harder pushing current into a high-impedance cell, and that extra work becomes heat. This is normal for the first two to three charge cycles and settles as the cell's impedance drops with use. If the device stays hot beyond the fifth cycle, check that the charge IC is not stuck in fast-charge mode with an uncalibrated fuel gauge — drop back to standard charge current for another full cycle.