Battery life

[Lebenz]

This is not strictly a MB question. I just bought a 12 volt battery for use with a generator. The battery is of the sealed variety and there is no means to add or remove water. The purpose of the battery is to run the generator’s starter motor. We haven’t needed to use this generator for years.

The question are:

1) will there be a difference in battery life if we just leave the battery unconnected verses connected?

2) how long would the new battery hold a charge, providing its not connected?

TIA