You can saved a dead lead acid battery and change it to alkaline.

There are videos online that show you how to do it. Just remember that a tiny drop of the acid can cause you to go blind so use eye protection and empty the battery acid into a bucket and then use a funnel to empty it into a container to dispose of at a recycling facility which should be FREE to drop off along your errands.

You can use common electrolytes for a solution to replace it.

If the battery is dead, after having drained it, neutralized the leftover acid residue inside, wash it out with high pressure water to unstick any corrosion bits that are shorting (touching) the plates inside.

Refill and charge it up.