Dr. Battery RPROAS350P-01 7.7V 3800mAh laptop battery

Replacement battery for VivoBook 14 and 15

This 7.7 V lithium-polymer pack is built as a direct replacement for the Asus C21N1818 cell used in VivoBook 14 X412FJ and VivoBook 15 F512FA and X512DA series laptops. It restores the original 29 Wh energy rating so the notebook regains its factory run-time. The black housing matches the OEM form factor and fits the listed sub-models without modification. Integrated protection circuits guard against short circuit, overheat and overload during daily use.

Upgrade from a worn or swollen original cell

When the original battery no longer holds a useful charge or shows physical swelling, this unit restores full mobility without requiring a higher-capacity chassis change. The swap is worthwhile when the laptop otherwise meets performance needs but tethering to an outlet has become necessary. It is not suited for users who need a larger capacity than the stock 29 Wh design provides.

3800 mAh capacity for typical office workloads

The 3800 mAh rating delivers enough headroom for several hours of document editing, web browsing and video playback on the compatible 14-inch and 15-inch VivoBooks. Runtime will diminish under sustained heavy loads such as gaming or video rendering, and the fixed 29 Wh limit means the pack cannot support extended off-grid sessions without recharging.