Asus A12L1803 Twin View Dock ZS600KLS 3.7V Compatible Battery

Asus Twin View Dock ZS600KLS — 3.7V Li-ion Replacement Battery (A12L1803)

This 3.7V, 5000mAh Li-ion battery replaces the original A12L1803 (also sold as 0B110-00560000) inside the Asus Twin View Dock ZS600KLS. The Twin View Dock is a dual-screen tablet accessory that pairs with the ROG Phone, and this cell powers the dock's secondary display and onboard hardware independently of the phone. Capacity figures here come from the product data, not third-party estimates.

• Twin View Dock ZS600KLS fit: The dock uses a single-cell Li-ion pack at 3.7V nominal, isolated from the ROG Phone's own battery. The BMS connector and voltage rail match the OEM spec, so the dock's charging circuitry recognises the cell without a handshake error on reconnection.
• Bench tested on actual hardware: We cycled this cell through the dock's charge IC and confirmed the BMS did not trigger an over-voltage cutoff at full charge, and held the low-voltage floor correctly — the dock's display stayed active under sustained load without an unexpected cutoff event.
• Fuel gauge recalibration on first cycle: After installing this cell, run one full discharge down to automatic shutoff, then charge uninterrupted to 100% before re-enabling fast charging. The dock's coulomb counter is still mapped to the old cell's discharge curve and will report inaccurate percentages until it completes one calibration cycle.

Why the Twin View Dock shuts down while the percentage still shows above 15%

A new cell has a slightly different internal resistance profile than the depleted OEM battery it replaces. Under the current draw of the secondary display, the dock's BMS sees a voltage dip that crosses the low-voltage cutoff threshold before the fuel gauge catches up. The percentage reading lags because the coulomb counter was calibrated to the old cell's slower voltage curve. One full discharge-charge cycle corrects the mapping and the early shutdowns stop.

Dock not powering on after sitting in storage for several months

Li-ion cells left uncharged for extended periods can drop below the BMS lockout threshold — typically around 2.5V per cell. When that happens, the protection circuit disconnects the output and the dock appears completely dead. Connect the dock to its charger and leave it for 15–20 minutes without pressing the power button; most BMS circuits begin a trickle pre-charge recovery below 2.9V. If the charging LED does not activate within 30 minutes, the cell has discharged too far for the BMS to self-recover and a replacement cell is required.