Mundane items in the world have plutonium fuel cells where they used to have no batteries or normal batteries.
This happens for items dropped by monster that have been killed as well as items found around in houses.
Mundane items should spawn with everyday batteries in them.

interesting, must be because magazine_default() orders all the magazines alphabetically and then picks the first one.
My observations last week in my limited messing around with guns and battery powered stuff was that the first item defined in the JSON to be loadable in an item was treated as the default magazine unless the number of charges specified to be loaded in the item would not fit in the default magazine.
This issue seems to be popping up in other items with their magazines defined with that in mind. Most notable i've seen so far is a M4A1 spawning with a 10 round magazine instead of a 30 round one.
Getting this 100% of the time in 10794.
It appears this issue is no longer present in 0.E-4787-g5cc59e1.
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My observations last week in my limited messing around with guns and battery powered stuff was that the first item defined in the JSON to be loadable in an item was treated as the default magazine unless the number of charges specified to be loaded in the item would not fit in the default magazine.
This issue seems to be popping up in other items with their magazines defined with that in mind. Most notable i've seen so far is a M4A1 spawning with a 10 round magazine instead of a 30 round one.