Kruger&Matz Live KM0023 Replacement Battery 3.7V 1800mAh

Kruger&Matz Live / KM0403 — 3.7V Li-ion Replacement Battery (KM0023 / BL-4N-i)

This is a 3.7V, 1800mAh Li-ion cell for the Kruger&Matz Live (KM0023) and the KM0403, KM0404, and Smartfren Andromax U. It replaces a degraded or failed original cell and restores normal smartphone operation. Capacity and voltage match the OEM specification exactly.

• KM0403, KM0404, and Andromax U compatibility: These models share the same 3.7V single-cell architecture, connector pinout, and BMS handshake as the Live (KM0023). The same cell fits all four without modification.
• Bench tested on actual hardware: We cycled this cell through a full discharge and charge sequence on a KM0403 unit. The BMS accepted the cell without fault flags, charge current ramped normally through CC/CV stages, and cutoff triggered at the correct termination voltage.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging and run one complete discharge-to-charge cycle. This allows the fuel gauge IC to recalibrate its coulomb counter against the new cell's discharge curve before high-current charging begins on an uncalibrated reference.

Sudden shutdown at 20–30% on the KM0023 replacement cell

A degraded or brand-new uncalibrated cell can cause the phone to cut out well before the percentage reaches zero. Under modem transmit load or screen-on bursts, the cell voltage drops faster than the fuel gauge IC expects, crossing the low-voltage cutoff threshold while the display still shows charge remaining. The fix is one full discharge-to-shutdown cycle followed by an uninterrupted charge to 100% with the screen off. After that cycle, the coulomb counter has a real discharge curve to reference and the shutdowns stop.

Phone not powering on after the replacement cell sat in storage

Li-ion cells ship at a partial state of charge and self-discharge slowly in storage. If the cell dropped below approximately 2.5V per cell while sitting on a shelf, the BMS may have entered lockout mode to prevent damage. Plug the phone into a wall charger — not a PC USB port — and leave it connected for at least 20 minutes without pressing the power button. The charge IC will trickle current into the cell until it clears the BMS lockout threshold, after which normal charging resumes.