Yamaha NAVIGO Owner's Manual page 66

(3) Storing the battery
Store batteries in a cool, dry area. (A location with a tem-
perature between 50 – 77°F (10 – 25°C) is optimal for
storing.)
Fully charge the battery that you do not plan to use for a
long period of time (30 days or more).
8
If you intend to store the battery for more than 3 months
without using it, fully charge the battery every 3 months.
Always put on the protective cap when storing the battery.
Protective cap
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