Naio wrote:
Trickle charger failed in storage, it is dead as a doornail.
What exactly is dead....the charger OR the battery ??
If it is the battery, it probably is a total loss.
Under those conditions, worrying about "conditioning" is probably a total waste of time.
To try and RECOVER the battery, put it on the highest capacity charger that you have for about 4 hours. If that charger is fully automatic, leave it connected for 12 hours or more to see if it comes back up to voltage or not (12.8 at least). But that's probably a waste of time too.