why does Car my engine stalls but power still on?

I have a 2004 crown victoria. And 30mins ago I was driving. Came up to a red light and as I braked the battery light came on and my engine stalled... BUT MY LIGHTS, RADIO AND DASHBOARD WERE STILL ON!!! . So I turned everything off. Started it up again and it works. About 2miles down the road. Another red light . I brake, battery light comes on, engine stalls Everything still on. Radio, dash lights and head lights,. Turn everything off. Repeat.. turns on once more. Basically it happens again for 3rd time. Repeat, starts up. After 3rd time I said for get all remaining red lights and stop signs and hauled *** home to avoid stopping. Got home all good no shut offs as long as I didn't brake to complete stop. Whats going on?! HELP!!!!

I don't know the answer to the majority of your questions, but I want to let you know that if you don't have a muffler, many people around you will be very displeased due to the noise (you'll look like a jerk even if you're a nice person)

Faulty temp gauge?

I have a 97 z28 Camaro with 203k on the body but under 40k on the rebuilt engine. The other day my temperature gauge stopped working. It's stopped on cold even after a good 15-20 minutes of a little stop and go driving. I checked the temperature sending unit, actually replaced it has a new thermostat too. The car doesn't overheat cause I still drive it. Just the temperature needle won't move. Idk what could be causing it. If someone knows, how can I fix it?