GPRS Shield V2 - 3V CR1220 Battery Holder Connetor


I would like to know what is the “3V CR1220 Battery Holder Connetor” on my GPRS Shield V2 ? (to get a better connection speed maybe ?)
Should I put a CR1220 Battery in it ?

Thank you in advance.


The battery is a back up one for RTC function. It’s connected to the VRTC pin of SIM900.
For the details please have a look in the shared datasheet files on the wiki.