How do I know if a laptop battery will fit my device?

The most reliable method is matching the part number printed on your original battery. Also confirm the voltage and compare the battery shape/connector position with the product photos and specs.

Where can I find the battery part number?

Shut down the laptop, unplug power, remove the battery (if removable), and read the label printed on the battery itself. That part number is the best way to confirm compatibility.

Are different battery voltages interchangeable?

No. You must match the voltage on your original battery. Note: 10.8V equals 11.1V, and 14.4V equals 14.8V.

What should I compare before ordering a replacement battery online?

Compare the original battery’s part number and voltage first, then verify size/shape, connector type and location, latch position, and orientation against the product photos and specifications.

Can I use my laptop model number instead of the battery part number?

You can use a laptop model number to narrow it down, but the battery part number is more precise. One laptop model can support multiple battery types, so the printed battery part number is best.

What quick settings can extend laptop battery life?

Enable Battery Saver/Power Saver, reduce screen brightness, close unused apps/tabs, turn off Wi-Fi/Bluetooth when not needed, and avoid heat buildup by keeping vents clear.

Asus VivoBook 14 X412FJ Series VivoBook 15 F512FA 15 X512DA Series Asus Y4100FA X412FJ A412FA Series C21N1818 [7.7V / 29Wh] Laptop Battery Replacement

(Bundle with Adapter for 50% Off) C21N1818-2 Battery for Asus VivoBook 14 A412 F412 R424D X412 Asus VivoBook 15 F512 R564 X512 Asus VivoBook S14 S412 Y4200 Y5200F X409 X509 X545 Series Laptop B21N1818-2 [7.7V] Compatible Battery

$45.50 USD

~~$71.50 USD~~ Sale $45.50 USD

*Price shown is for the Battery only. The AC adapter is offered at a discount when clicking the 'Add to Cart' button.*

Product variants

Remark: There are 4 types of batteries for the same laptop model: C21N1818, C21N1818-1, C21N1818-2 and C21N1818-3. Please check for the Original part# and shape of the battery before please the order.
This battery ONLY compatible with Asus B21N1818-2 and C21N1818-2