IF you didn't plan ahead and bring a charger pack or can't find someone to jump your battery, then here's a tip that might save your bacon.

This really works but as the article says, you may damage the battery? Still if your in a bad situation/place, buying a new battery is a small price to pay to get out of it.
Some new batteries (sealed) don't have the individual cell caps, instead the have a couple of flat pieces that cover the cells.
You can use a some sort of pry bar carefully to pry then off and expose the individual cells. I do it every winter to add battery acid if needed.
Before you try this trick, I'd check the battery terminals for tightness/corrosion?
Your only going to get one chance with this last ditch emergency method, so you want the best connection possible.
If connections are tight but corroded and you don't have a wire brush, pour a bottle of Coke/Pepsi over terminals and it will dissolve the corrosion.
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