Sony Ericsson Xperia T LT30p Replacement Battery 3.7V 1780mAh

Sony Ericsson Xperia T LT30p — 3.7V Li-Polymer Replacement Battery (LIS1499ERPC)

This is a 3.7V, 1780mAh Li-Polymer cell replacing the original LIS1499ERPC battery in the Xperia T LT30p and related models. It fits the LT30p, Xperia TL (LT30a), and Mint variants that share the same connector and cell footprint. Capacity is 1780mAh — matching the original specification from the factory.

• LT30p, LT30a, and Mint compatibility: These models share a common battery bay, connector pinout, and BMS handshake protocol. The fuel gauge IC on each device reads the same charge curve, so one cell covers all three variants without modification.
• Bench tested on actual hardware: We cycled this cell on an LT30p and monitored the BMS charge termination. The protection circuit tripped correctly at 4.2V and resumed at 3.0V under load — both within spec for Li-Polymer cells of this capacity.
• Fuel gauge recalibration on first cycle: On first use after installation, run one full discharge to 10% before charging back to 100%. The Xperia T's fuel gauge IC calibrates its coulomb counter against the new cell's actual discharge curve — skipping this step causes erratic percentage readings for the first several days.

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

A new Li-Polymer cell has a slightly different voltage-to-capacity curve than the worn cell the phone originally calibrated against. When the modem fires at full power or the screen brightness spikes, the phone draws current the fuel gauge IC didn't account for, and the cell voltage drops faster than the OS expects. The device reads this as a voltage cliff and shuts off to protect the cell. Running one complete discharge-to-charge cycle resets the coulomb counter and maps the new curve correctly — shutdowns at 20–30% should stop after that first full cycle.

Device not powering on after the replacement cell sat in storage

Li-Polymer cells self-discharge in storage, and if the cell voltage drops below 2.5V the BMS enters lockout mode to prevent damage — the phone will show nothing when you press power. Connect the phone to a wall charger, not a PC USB port, and leave it for 20–30 minutes without pressing any buttons. The charge IC needs to trickle current into the cell before the BMS will re-initialise and allow the phone to boot. If the charging indicator appears, voltage has recovered above the lockout threshold — typically around 2.8V — and normal charging will resume.