reversed battery polarity

[Mrtopsodapop]

I done messed up a little here...
2 questions at the end
So I got a new battery for the car about a month ago, ran her once then didn’t have time until yesterday... battery was flat

No problem took it inside to charge as I connected the - to the + and the + to the - for about 30 seconds before I realised and swapped em around

Been about 12 hours since and I’ve just checked with a meter and it’s reading -12.84 but when I swap and read the - with the + rod it reads 12.84

Soo yeaaa I can’t afford a new battery right now and from my searching I can drain it and charge it up the right way and it should swap the polarity back right?
1. Can I just put the battery in backwards?
And
2. If I can put it in backwards can I use the lights overnight to drain it

 

[accentstencil]

I don't think there is any way that a battery can change polarity. Are you sure the probes are in the correct inputs in the multimeter?
Maybe check with a different multimeter.

 

[losh1971]

I have come across a battery years ago that was reverse polarity. However it came from the factory like it. I fitted it to my old bus at the mech workshop ans it blew my alt. I have never heard of a battery charger doing the former to a good battery. AFAIK the new switch mode chargers won't operate if the poles were around the wrong way. I think on my old school charger it would blow or arc all over the place if i tried.

 

[wildfiremaint]

The voltage readings are perfectly normal.
If you have the + multimeter probe connected to the + terminal on the battery then the meter will read +12V.
If you connect the + probe to the battery - terminal then the multimeter will indicate - 12V.

No harm done by connecting mutimeter back to front.