FBP Backup Battery can only be used at very low charge

[FenodyreeAv]

Brief description of the issue

The Backup Battery is only usable at the very low end of nutrition, well below the point where you are in red hunger and slowed down.

What you expected to happen

To be able to use the backup battery when you are in red hunger.

What actually happened

To not be able to use it until you've been in red hunger for about half an hour.

Steps to reproduce

Be an FBP, do not charge for a while.

Additional info:

• Server Revision: Found using the "Show Server Revision" verb under the OOC tab.
• Anything else you may wish to add (Location if it's a mapping issue, etc)

[Atermonera]

So a simple search of our github didn't tell me what nutrition values the different effects proc at, but looking at the code, the backup cell can only be used when you have <100 nutrition, and it's a single-use +100 nutrition. #4946 seems to indicate that this is (or was) intended behaviour

[Dunmeritude]

It is not actually single use, it can be recharged. But its generally near useless seeing as you'll have been in red hunger for a long time by the time you are able to use it.