ZTHY B31N1911 ASUS VivoBook Replacement Battery 11.55V 42Wh

ZTHY B31N1911 is a direct replacement Li-ion laptop battery designed to restore power and run-time for a wide range of ASUS VivoBook Flip 14 and VivoBook 15 models.

If your VivoBook shows shortened battery life, won't hold charge, or the original pack has failed, the ZTHY B31N1911 (C31N1911) offers a compatible, 11.55V 42Wh (3640mAh) replacement engineered to match the form, connector and voltage of the original. Built for straightforward swap-in installation, this pack suits many K413, F413, X413, A413, S413, X421, M413 and X1502 series machines. Below you'll find clear answers about fit, performance, installation and who should consider this battery.

How do I know this battery fits my ASUS model?

Compatibility is based on part numbers and the physical connector; the ZTHY B31N1911 replaces C31N1911 and compatible OEM codes listed in product specs. Check your original battery label for matching part numbers or confirm your laptop’s model family against the compatibility list.

• Replaces part numbers: B31N1911, C31N1911, 0B200-03580000, 0B200-03750000, B0B200-03580300
• Commonly compatible with Asus VivoBook Flip 14 and VivoBook 15 series like A413, K413, F413, X413, S413, X421, M413, X1502
• Verify model label inside the battery compartment or system BIOS for exact match

What performance and safety specifications should I expect?

This ZTHY replacement is a lithium-ion battery rated at 11.55 volts and 42Wh (3640mAh), matching typical OEM electrical characteristics so the laptop manages charge and discharge normally. It is intended as a like-for-like replacement rather than an aftermarket improvement in capacity or run-time.

• Battery type: Li-ion for standard laptop power profiles
• Voltage: 11.55V — consistent with original ASUS specifications
• Capacity: 42Wh / 3640mAh — designed to restore original battery life expectations

How should I install and initialize the new battery for best results?

Installation is usually a simple swap, but proper seating and initial cycling help the system recognize the new pack and condition its internal controller. If the laptop does not immediately detect the battery, reseat the connector and run a charge/discharge cycle as described below.

• Power down, remove the old battery if accessible, and connect ZTHY unit firmly to the battery interface
• If not detected at first boot, reinstall and ensure the connector is fully seated
• Conditioning tip: discharge to about 10–20% (avoid 0%), then fully charge; repeat 3–4 cycles to stabilize capacity reporting

Will this battery affect my laptop’s performance or warranty?

A properly matched replacement battery restores run-time without altering CPU or GPU performance; it supplies power according to the laptop’s existing power-management settings. Installing third-party parts can affect manufacturer warranty terms depending on ASUS policies—check your warranty before replacing components.

• Supplies matched voltage to maintain normal performance
• Does not change system power profiles or hardware specs
• Check ASUS warranty terms before self-replacement to confirm coverage

Who is this for: The ZTHY B31N1911 replacement battery is aimed at VivoBook owners who need a reliable, compatible swap for a failed or aging pack — technicians replacing batteries, students and professionals restoring mobility to their ASUS laptops, and anyone who prefers to repair rather than replace their machine. This option is best when your laptop model and original part number match the listed compatibility, and you are comfortable performing a safe battery swap or having a technician do it.