TLP040D2 Alcatel One Touch Pixi 3 7 Compatible Battery 3.8V 4000mAh

Alcatel One Touch Pixi 3 7 — 3.8V Li-Polymer Replacement Battery (TLP040D2)

This 3.8V, 4000mAh (15.2Wh) lithium-polymer battery replaces the TLP040D2 cell in the Alcatel One Touch Pixi 3 7 tablet, covering models 9007T and OT-9007. The original cell degrades through repeated shallow cycling — this replacement restores full charge capacity to the 7-inch tablet. Dimensions are 100.80 × 76.70 × 3.70 mm, matching the stock cell footprint.

• 9007T and OT-9007 compatibility: Both variants share the same battery bay dimensions, 3.8V nominal voltage rail, and TLP040D2 connector pinout — the BMS handshake passes without modification on either board revision.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the OT-9007 board. The BMS accepted the new cell without flag errors, and the charge IC reached full cutoff voltage cleanly at 4.35V.
• First-cycle fast-charge protocol: On first use after installation, disable fast charging for one complete discharge-charge cycle. The fuel gauge IC is calibrated to the old cell's discharge curve — running one full cycle at standard current lets it recalibrate before high-current charging pushes into an uncalibrated cell.

Sudden shutdown at 20–30% on the Pixi 3 7 after a cell swap

The Pixi 3 7 fuel gauge IC holds a discharge curve learned from the original cell. When a new cell is installed, that stored curve no longer matches the actual voltage-versus-capacity profile of the replacement. Under screen backlight or network load, the cell voltage drops faster than the IC expects, crossing the low-voltage cutoff threshold well before the reported percentage hits zero. One full discharge-to-shutdown followed by an uninterrupted charge to 100% forces the coulomb counter to resync against the new cell's actual curve.

Battery percentage jumping erratically on the OT-9007 after replacement

Erratic percentage readings — jumping from 45% to 60% or dropping 15 points in seconds — point to the fuel gauge IC recalibrating against a cell it has never seen before. The IC uses accumulated charge and discharge data to estimate state-of-charge; with a new cell, that data is stale and produces unstable readings. This is not a fault with the replacement cell itself. Let the tablet complete two full discharge-charge cycles without interruption and the reported percentage will stabilise.