Yes, RTC battery should be provided for RTC_PWR which can then be used by RTC controller on SOM.
G50M SOM will not support battery charging. A 2-pin header for CR2032 battery connection is available on the G50D carrier card for support.
For further inquiries, please get in touch with mktg@iwave-global.com
Please find the detailed G50M product information in the below link,