Rechargeable battery. Top it off before each show and never* lose power mid-recording again.
* until the battery cell dies (which has happened to me).
This.
Been using rechargeables for 15 years & never had any issues.
9v though? I've been using AA/AAA rechargeables for a long time too and never really had any issues either, but for some reason, I've never tried rechargeable 9v's
I'm sure their performance is much better than it used to be though, so I've been thinking of giving them a try. It costs me not much at all a show though and 1x9v alkaline lasts me 1 whole day of recording at Summer Camp
Plus, Mr. Naiant said that using [1] rechargeable 9v wouldn't give the Littlebox enough juice for my Schoeps actives, so I've just stuck with alkalines so far!