Find out available mobile network bands in my area and disable scanning for unused bands

I have an HTC 626g+ which was supposed to be released in India, but I'm using it in Russia, which probably has different cellular frequencies available. I've read on certain forums that smartphones try to scan and find the best band available, and sometimes they are set to scan for bands that are not supposed to work at all, which allegedly wastes precious battery life. I would like to know if disabling scanning for unused bands would save any significant amount of battery life (10 minutes is significant IMO) and if so, how to figure out which bands can be used.