Haier Lingyue S4 Replacement Battery 11.4V 2600mAh

Haier Lingyue S4 — 11.4V Li-Polymer Replacement Battery

This is a 11.4V, 2600mAh (29.64Wh) Li-Polymer battery for the Haier Lingyue S4 notebook. It replaces the original cell when charge capacity has degraded or the pack no longer holds voltage under load. Dimensions are 181.40 x 85.55 x 10.10mm — confirm these against your existing pack before installing.

• Lingyue S4 fitment: The S4 uses an internal Li-Polymer pack wired directly to the board's charge controller. The connector pinout and BMS handshake must match the original — this cell replicates that interface so the charge IC recognises it without a firmware error.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on a notebook charge controller. The BMS reported correct cell voltage, charge current tapered normally at top-of-charge, and the pack accepted a full 29.64Wh without thermal event or premature cutoff.
• First-cycle reset after install: After fitting this cell, run the laptop down to hibernate cutoff, then charge uninterrupted to 100% without using the machine. This forces the BIOS battery learn cycle to recalibrate against the new cell and clears the inaccurate health warning that appears after every pack swap.

BIOS reporting poor battery health immediately after fitting the new cell

The BIOS reads health data stored in the battery pack's EEPROM. When a new cell arrives, that EEPROM holds factory defaults — cycle count zero, rated Wh figures — which the BIOS hasn't yet mapped to actual charge behaviour. The system flags this mismatch as a health warning. It is not a fault with the cell itself. Run two full discharge-to-hibernate and charge-to-100% cycles and the BIOS will update its learned data, clearing the warning.

Laptop shutting down at 20–30% shown on the fuel gauge

This happens when the fuel gauge IC still holds voltage-curve data from the old, degraded cell. The new cell hits a different voltage cliff under combined CPU and display load, so the gauge misreads remaining capacity and triggers shutdown earlier than expected. The fix is calibration — let the battery discharge fully to hibernate cutoff under normal use, then charge straight to 100%. After two or three of these cycles the fuel gauge IC recalibrates its curve to the new cell and the shutdown point corrects itself. If it persists after three cycles, check that charge reached a full 11.4V at the pack terminals.