I bought a battery pack Thingie from Best Buy.
I got it because my old phone would not keep a good charge.
And because the job I was at I did not want to plug my phone in to charge with it being out of my site.
It was Just Okay.
Here is what I use Now when I need to.
Link:
https://www.amazon.com/GOOLOO-GP4000...167581669&th=1
This can Jump your vehicles off and charge your Phone and other stuff.
I don't leave home without it.
It worth the extra money IMHO because of it's Multi functionally