KAZAM Trooper 451 Replacement Battery 3.7V 1800mAh TR4501

KAZAM Trooper 451 — 3.7V Li-ion Replacement Battery (TR4501)

This is a 3.7V, 1800mAh Li-ion replacement battery for the KAZAM Trooper 451 and Trooper 451 Dual SIM smartphones. OEM part numbers TR4501 and TR4501-CHHCD0006517 both cross to this cell. Fit this when the original battery no longer holds a useful charge or fails to power the phone at all.

• Trooper 451 and 451 Dual SIM compatibility: Both variants share the same battery bay dimensions (71.00 × 52.90 × 4.50mm), connector pinout, and BMS handshake protocol — this single cell covers either version without modification.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge on the Trooper 451 platform. The BMS accepted the cell without error flags, and the charge IC completed a full constant-current to constant-voltage transition correctly.
• Fuel gauge recalibration on first use: Disable fast charging for the first complete discharge-charge cycle after fitting this cell. The fuel gauge IC is still calibrated to the old cell's discharge curve — running one full cycle at standard current lets it remap against the new cell before high-current charging begins.

Why the Trooper 451 reports wrong battery percentage after a cell swap

The Trooper 451 uses a fuel gauge IC that tracks charge state by comparing measured voltage against a stored discharge curve from the original cell. Swap in a new cell and that curve no longer matches — the gauge reads against old data and displays an inaccurate percentage. This is not a fault with the replacement cell. One full discharge down to automatic shutdown, followed by a full charge to 100%, rewrites the reference curve and brings the percentage reading back into line.

Sudden shutdown at 20–30% on the replacement cell

This happens when the modem or display pulls a short high-current burst and the cell voltage drops sharply below the BMS protection threshold — even though the gauge still shows charge remaining. It is a voltage-sag event, not a capacity problem. New cells can exhibit this until the electrolyte fully wets the electrode stack after a few cycles. If shutdowns persist past three full cycles, check that the battery contacts are clean and that measured open-circuit voltage sits above 3.6V before the phone powers on.