TCL M823 Replacement Battery 3.8V 3500mAh TLP035A1

TCL M823 / N1 Max — 3.8V Li-Polymer Replacement Battery (TLP035A1)

This is a 3.8V, 3500mAh Li-Polymer replacement battery for the TCL M823 and N1 Max smartphones. It replaces OEM part TLP035A1 and fits the original battery compartment at 91.10 × 64.90 × 3.67mm. Voltage and capacity match the original cell specification exactly.

• M823 and N1 Max fit: Both models share the TLP035A1 footprint, the same 3.8V nominal voltage rail, and an identical BMS connector pinout. One cell covers both devices without modification.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the M823 platform. The BMS handshake completed correctly, charge current was accepted without fault codes, and the protection circuit tripped at the expected cutoff thresholds.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging and complete one full discharge-charge cycle at standard rate. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging begins on an uncalibrated cell.

Sudden shutdown at 20–30% on the TCL M823 after a cell swap

The M823's fuel gauge IC stores a discharge model calibrated to the original cell. A new cell with a slightly different internal resistance profile causes the IC to miscalculate remaining capacity. When the modem fires a high-current burst — during a call or LTE handoff — the actual cell voltage drops below the shutdown threshold even though the displayed percentage reads mid-range. The fix is one full discharge to automatic power-off followed by a complete charge to 100% at standard rate. After that cycle, the coulomb counter resets against the new cell and percentage readings stabilise.

TCL M823 not powering on after the replacement battery sat in storage

Li-Polymer cells in storage self-discharge over time. If the cell drops below approximately 2.5V, the BMS enters lockout mode and blocks current flow to protect the cell from damage. Plugging in the charger may show no response at all — no charging indicator, no boot. Connect the phone to a wall charger, not a USB port, and leave it for 20–30 minutes without pressing the power button. The charge IC trickle-feeds current at a safe low rate until the cell climbs above the BMS re-enable threshold, typically around 2.8–3.0V, at which point normal charging resumes.