Samsung Galaxy S III Replacement Battery EB-L1G6LLUC 3.8V 2100mAh

Telstra Galaxy S III — 3.8V Li-ion Replacement Battery (EB-L1G6LLUC)

This is a 3.8V, 2100mAh Li-ion cell for the Samsung Galaxy S III, sold under the Telstra network variant GT-i9300T and related S3 models. It replaces a degraded or failed original cell when the phone can no longer hold charge through a normal day. OEM part numbers EB-L1G6LVA, EB-L1G6LLK, EB-L1G6LLA, and EB585158LP all cross-reference to this same cell format.

• GT-i9300T and S III variant fit: The GT-i9300T shares the same battery bay dimensions, connector polarity, and BMS contact layout as the broader Galaxy S III lineup. All listed variants use the same 63.00 × 50.40 × 5.40mm footprint — no modification to the chassis or contacts needed.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on GT-i9300T hardware. The BMS accepted charge handshake without fault codes, and the protection circuit triggered correctly at low-voltage cutoff — no runaway, no false full-charge termination.
• Fuel gauge recalibration on first install: On first use after fitting this cell, run one full discharge down to automatic shutoff, then charge uninterrupted to 100% without fast charging enabled. The Galaxy S III's fuel gauge IC was calibrated to your old cell's curve — skipping this step causes the percentage counter to read incorrectly for weeks.

Sudden shutdown at 20–30% on the Galaxy S III after a cell swap

The Galaxy S III uses a coulomb-counter-based fuel gauge that learns the discharge curve of the installed cell over time. When a new cell goes in, the counter is still mapped to the old cell's voltage-versus-capacity curve. Under high-current load — active LTE, GPS, or screen-on gaming — the new cell's voltage can drop sharply below what the old curve predicted, triggering emergency shutdown before the gauge reaches zero. This is a calibration gap, not a defective cell. One complete discharge-to-shutoff followed by a full uninterrupted charge corrects the coulomb counter's baseline. After two full cycles, shutdowns at 20–30% should stop entirely.

Phone stays warm near the battery compartment during the first few charges

A new Li-ion cell starts with higher internal impedance than a cell that has completed several charge cycles. The Galaxy S III's charge IC pushes current into this higher-impedance cell, and the extra resistance converts some of that energy to heat. This is normal for the first two to three charge cycles and not a sign of a faulty cell or charger fault. Warmth near the battery cover — not the screen or processor area — during charging is the expected location. If the phone becomes hot to hold or shows a temperature warning on screen, stop charging and check that the replacement cell is seated flat with no debris under the contacts.