Battle damage is the damage a monster takes during a battle. It is not the same as a monster's Attack or Defense Points.
Here's how battles work in Yu-Gi-Oh!:
1. Declaration of Attack: A player declares an attack with a monster.
2. Declaration of Defense: The opponent can choose to defend with a monster or not.
3. Battle Calculation: The attacking monster's Attack Points are compared to the defending monster's Defense Points.
4. Battle Damage: The difference between the two is dealt as battle damage to the monster with the lower value. If the difference is zero, no battle damage is dealt.
5. Destruction: A monster is only destroyed if its Life Points are reduced to zero or it is specifically destroyed by an effect.
In short, battle damage is not the same as life points and does not directly lead to a monster's destruction.