Why do some XLR connectors take batteries?

Question

New to audio recording, and have a question regarding my mics.

A few months back I acquired two Audio Technica AT899 lav mics, that I connect to a Zoom h4n. I use these to record interviews.

I will soon have need to record a broader panel discussion, so I've gone ahead and ordered a Zoom h6 and two Rode lav mics. I've also ordered two Rode Micon-5 XLR connectors.

My intention is to plug the 4 lav mics into the h6 so that I can record four people at once.

My question is as follows: why is it that my AT899 lav mics use XLR connectors that need batteries, whereas the Rode XLRs don't seem to require them?

Is this something to do with phantom power, ie. the AT899s can operate via battery or phantom power, whereas the Rode can only use phantom? If this is the case, what are the repercussions of using lav mics on phantom power? Does it simply mean that the battery on my Zoom will be reduced quicker? I usually operate the Zoom on battery when using the AT899s, also placing batteries in the XLR connectors. If I do start using phantom power (which it looks like I need to use for the Rode mics), am I better off powering the Zoom via an AC adapter?

Thanks in advance!

Answer 1

Yes, microphones like the AT899 give you the option of using internal battery power OR phantom power (from the XLR).

Yes, microphones like the Rode Lav require phantom power without the option.

Yes, the more phantom power is sucked out of your Zoom H6, the faster it drains the available battery power. You are almost always better off running equipment from mains power. The batteries give you the extra option of "backup" if the mains power fails.