The Compass tricycle is prepared/wired up to accept a second battery if desired. It ships with what seems to be two batteries, however the right one is an empty case. The left battery is the viable one and is retained on the tricycle with a locking mechanism. When using the tricycle make sure the power switch (on the left battery) on the tricycle is switched on.

If the 2nd battery upgrade kit is purchased, the lock mechanism will have to be installed on the existing battery dock on the tricycle. This requires opening the battery dock by removing 6 phillips bolts. The lock mechanism is installed using 2 phillips bolts. The battery dock is then closed back up and new battery inserted and locked into place. The batteries will have to be charged independently from one another and most likely the key for second battery will not match the first, so they will use different keys.