Save any work you may be doing, and then close all running programs or applications.
Disconnect the AC Adapter.
Smart Battery Calibration will not run when the AC adapter is connected.
Restart and run Samsung BIOS configuration.
Restart the PC, and then press F2 when the SAMSUNG logo appears. This will start the Samsung BIOS Configuration.
Run the Smart Battery Calibration.
Click Advanced on the left-side menu, and then double-click on Smart Battery Calibration on the right-side menu. The battery will be discharged by the PC. The process may take up to 5 hours depending on the capacity and remaining battery life. To cancel the operation, press the ESC key.
Charge the battery.
After the battery has been completely discharged, connect the AC adapter to your PC and charge the battery. You can use the PC while the battery charges, or leave it off until fully charged.
Source from https://www.samsung.com/us/support/search/?searchTerm=Series 9 Notebook NP940X3N&page=1&sort=relevance&SiteType=support&SupportTopics=Power %26 Battery&ModelCode=N0052760
Here is the brand new samsung NP940X3N laptop battery detail we have for now, it is brand new, and it should be allowed to replace with part number AA-PBTN4LR.
Price: 105 USD
Voltage: 15.4V
Capacity: 3530mAh (54Wh)
Battery cells: 2-cell
Chemical: Li-ion
Battery Color: white
Condition: new original battery
Warranty: 9 months
The battery is available here: https://www.storebattery.co.nz/samsung-aa-pbtn4lr-15.4v-3530mah-laptop-battery-store-for-new-zealand-p-210242.html