When you drop something after reloading (for example, a battery in a welder) it doesn’t fall in the same way as if you just drop it from your inventory.
To test this, stand on top of a recharging station in a vehicle and reload your welder (or whatever). Choose to drop the old battery. Normally you’d expect it to land in the recharger to charge up, but instead it lands on the pavement underneath the vehicle.