but the ability to affect weight is mostly in the components, and the battery is the largest and heaviest of these. aluminum is pretty light but you need a certain amount of it to have the structural characteristics they're aiming for.
The 13" Ryzen 7 5700U LG Gram weighs 980 grams with a 51 kWh battery. The 13" M2 MBA weighs 1200g with a 52.6 kWh battery. The main weight difference is not from the 1.6 kWh of battery but the choice of aluminum over magnesium alloy. I'm sure things will be similar for the 15" MBA vs. 15" LG Gram.
