Battery Charger
Of the non-ducati chargers. Optimate by Techmate are the best. I use a Optimate4. They are a true charger/maintainer. The battery is tested every 30 minutes. Voltage is only applied if needed, they are designed maintain batteries at 13.6 volts.
This reduces heat cycles that batteries are subject to when using other chargers. Heat cycles will kill batteries, that's why people claim "battery tenders" should not be used.
A Desulfating feature is built in the Optimate3, 4,5,6 series chargers if needed.
They also sell a Lithium battery charger now as well.