Also known as T501-Non-Rechargeable Energy Storage Unit, each Single-Use Battery can store up to 1000 EU. That's 9000 EU less than their rechargeable counterparts. They can only be used once but are stackable and easy to produce in large quantities.
One may be tempted to burn the ingredients for EU in a generator but the total EU value of the batteries created is greater then the resources needed to make the batteries.
Coal= 4000 EU in generator
Redstone = 500 EU in generator
Coal dust= -625 to macerate from coal
Ignoring Hydration of the dust the total EU value of this is 4000+500-625=3875 EU
Since one Single-use battery is worth 1000 EU and 8 are created with this recipe this gives a total value of 8000EU which is 4125 EU more then the ingredients give if you burn them into EU. Thus you gain energy by creating them due to some complex laws of energy conservation getting broken in their creation.