How can I stop an int from adding with the getkeydown

When I collect a battery it goes into the int Battery Count. When the current battery power reaches 0 and the battery count is greater than 0 the battery count reduces and current battery power increases 100%. That works. But what I want is for when the current battery power reduces to 50% I want to press the “T” key and use one of the Battery Count and increase back to 100%. What happens is that I can continue press “T” and the count goes into a negative number and the Current battery power goes to 100% instead of ending at 0 battery counts and 0 % current battery Power. I know I need an ELSE in the script but there is where I get in trouble with it. Part of the script is below.

public float _currantBatteryPower = 0f;
public static int BatteryCount;
void Update(){

if (_currantBatteryPower <= 0 && BatteryCount > 0)
{
BatteryCount–;
_currantBatteryPower = 100;
}
if (Input.GetKeyDown(KeyCode.T) && _currantBatteryPower <= 50 )
{

        GetComponent<AudioSource>().PlayOneShot(_PickupSound);
        BatteryCount--;
        _currantBatteryPower = 100;
    }

You can either add another condition to the second if statement like

if (Input.GetKeyDown(KeyCode.T) && _currantBatteryPower <= 50 && BatteryCount > 0)

or you avoid redundant code and do it like this, for example:

public float _currentBatteryPower = 0f; 
public static int BatteryCount; 

void Update()
{
    UseBattery(0f);

    if (Input.GetKeyDown(KeyCode.T))
        UseBattery(50f);
 }

 private void UseBattery(float threshold)
 {
     if (_currentBatteryPower <= threshold && BatteryCount > 0)
     {
         BatteryCount--;
         _currentBatteryPower = 100;
      }
  }

(i renamed currantBatteryPower to currentBatteryPower with e, either change it again or make sure the other scripts use the same name)

Thank You, Thank You, this was driving me batty, and now I can relax and play Bat Man this fine Sunday Morning.