Asus PadFone Infinity A80 Compatible Battery 3.75V 5050mAh

Asus PadFone Infinity A80 Tablet — 3.75V Li-Polymer Replacement Battery (C11-P05)

This 3.75V, 5050mAh (18.94Wh) lithium-polymer cell replaces the OEM C11-P05 battery in the Asus PadFone Infinity A80 Tablet and PadFone Infinity A80 10.1. It powers the tablet portion of the PadFone hybrid dock system, supplying the display, Snapdragon SoC, and wireless radios. Replace this when the original no longer holds charge or prevents the tablet from powering on.

• PadFone Infinity A80 tablet dock fit: Both listed models — the A80 Tablet and A80 10.1 — share the same tablet slab housing, connector pinout, and BMS handshake protocol, which is why a single C11-P05 cell covers both. The dock station draws from the phone battery separately; this cell covers the tablet half only.
• Bench tested on actual hardware: We cycled the C11-P05 replacement through charge and discharge on the A80 tablet dock. The BMS accepted the cell without fault flags, charge current stepped down correctly at the top-of-charge threshold, and the protection circuit tripped as expected at the low-voltage cutoff.
• Fuel gauge recalibration after install: After fitting this cell, run the tablet down to automatic shutoff, then charge uninterrupted to 100% in a single session. This forces the fuel gauge IC to recalibrate against the new cell's actual capacity curve and clears the inaccurate percentage readings that appear immediately after a swap.

Tablet shutting down at 15–25% remaining on the A80

The A80's fuel gauge IC was calibrated to the original cell's discharge curve. A new cell has a slightly different voltage-to-capacity slope, so the IC misreads remaining charge and triggers a shutdown before the cell is actually empty. This happens most often when the display brightness is high and Wi-Fi is active simultaneously — the combined load causes a brief voltage dip that the miscalibrated gauge interprets as a critical low. Running one full discharge-to-shutoff cycle followed by an uninterrupted charge to 100% re-anchors the gauge to the new cell. After that cycle, shutdowns at 15–25% stop.

Fast charging not available after battery swap on the A80 Tablet

The A80 tablet charge IC uses a handshake sequence with the charger during the first accepted charge cycle to confirm cell parameters before enabling higher charge current. On a fresh replacement cell, that handshake sometimes defaults to standard charge rate until one full cycle completes. If fast charge does not resume after the first full cycle, check that the charger output is at least 5V/2A — the tablet will silently fall back to slow charge on anything below that. Confirm the charger negotiation by checking that the tablet body stays only mildly warm during charge, not cool, which indicates a slow-charge fallback.