How to charge the battery in the smartphone hub on an Allant 9.9S.

[72 and Riding]

I recently purchased an Allant 9.9s and manual says to charge the smartphone hub's battery every three months if it is not to be ridden. I will not be riding my bike from Dec. - Mar. Question is, What type of connector connects to the smartphone hub. I have looked at the short apple to Smartphone hub which came with the bike, however I do not know what kind of connector is on the hub end. Thank you for any and all assistance.