what should you do when you use a Acer predator triton 300 se pt314-51s for the first time?

Before you use a battery pack for the first time, there is a conditioning process that you should follow:

1. Connect the AC adapter and fully charge the battery.
2. Turn on the computer and complete setting up the operating system.
3. Disconnect the AC adapter.
4. Operate the computer using battery power.
5. Fully deplete the battery until the battery-low warning appears.
6. Reconnect the AC adapter and fully charge the battery again.

 

The above sources from official manual. 

Acer predator triton 300 se pt314-51s battery

Brand new acer predator triton 300 se pt314-51s 15.48V 3886mAh laptop batteries
    

    Price: 109 NZD
    Voltage: 15.48V
    Capacity: 3886mAh (60Wh)
    Battery cells: 4-cell
    Chemical: Li-Polymer
    Battery Color: black
    Condition: new original battery
    Warranty: 9 months
   
You may have more details about the battery here: https://www.storebattery.co.nz/acer-predator-triton-300-se-pt314-51s-15.48v-3886mah-laptop-battery-store-for-new-zealand-p-460292.html