Sony Ericsson Xperia M5 Replacement Battery AGPB016-A001 3.8V 2600mAh

Sony Ericsson Xperia M5 / M5 Dual — 3.8V Li-Polymer Replacement Battery (AGPB016-A001)

This is a 3.8V, 2600mAh lithium-polymer replacement battery for the Sony Ericsson Xperia M5 and Xperia M5 Dual (E5633, E5606, and related variants). It replaces OEM part AGPB016-A001 using the same cell footprint: 115.00 × 36.00 × 4.25 mm. Capacity is rated at 9.88Wh.

• M5 and M5 Dual compatibility: Both variants share the same battery bay dimensions, voltage rail, and BMS connector pinout. The AGPB016-A001 part number covers the full range — single-SIM and dual-SIM models use identical battery hardware, so one cell fits both.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the M5 platform. The BMS handshake completed without error, charge IC accepted the cell on the first cycle, and the fuel gauge IC began tracking state-of-charge correctly after one full discharge-to-charge pass.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging and run one complete discharge-charge cycle at standard rate. This lets the coulomb counter recalibrate its discharge curve against the new cell before fast-charge current is applied to an uncalibrated state-of-charge register.

Sudden shutdown at 20–30% on the Xperia M5 after a cell swap

This happens because the fuel gauge IC is still reading the discharge curve of the old, degraded cell. A fresh lithium-polymer cell has a steeper voltage cliff at low charge states than a worn cell does. When the modem fires a high-current burst or the display brightness peaks, the new cell's terminal voltage drops sharply — the BMS interprets this as a critical undervoltage condition and cuts power before the percentage reaches zero. One full discharge-charge cycle at standard rate resets the coulomb counter and maps the new cell's actual curve. After that cycle, shutdowns at 20–30% stop.

Phone not powering on after the replacement battery sat in storage

Lithium-polymer cells self-discharge during storage. If a cell drops below approximately 2.5V per cell, the BMS enters a lockout state to prevent charging a critically depleted cell at full current. The Xperia M5 may show no charge indicator and appear completely dead. Connect the phone to a wall charger — not a PC USB port — and leave it for 20–30 minutes without attempting to power it on. The charge IC will trickle current into the cell at a low rate until voltage recovers above the BMS re-enable threshold, typically around 3.0V, after which normal charging resumes.