Ducati DIAVEL Owner's Manual page 205

Important
If battery is not kept at a minimum charge level
by a suitable battery charge maintainer, sulphation
may occur and this is an irreversible phenomenon
causing decreasing battery performance.
Note
When the motorcycle is left unused
(approximately for more than 30 days) we
recommend owners to use the Ducati battery charge
maintainer (Battery maintainer kit part no. 69924601A
- various countries; Battery maintainer kit part no.
69924601AX - for Japan, China and Australia only);
since its electronics monitors the battery voltage and
features a maximum charge current of 1.5 Ah.
Connect the maintainer to the diagnostics socket
located in the tail of the bike.
Note
Using charge maintainers not approved by
Ducati could damage the electric system; motorcycle
warranty does not cover the battery if damaged due
to failure to comply with the above indications, since
it is considered as wrong maintenance.
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