Don't Throw Out Your Solar Lights Just Yet.
I thought my solar light batteries needed replaced until I saw the battery compartments were corroded. So I took to the internet and found 2 options, white vinegar or baking soda and water mixture, neither worked. Then I remembered the old remedy I had used to remove tarnish from brass, ketchup. I didn't want to throw them away because they were still in great shape and I didn't want to have to buy more,
I slathered the ketchup on the contacts and the springs with a Qtip. Then let them sit for quite a bit of time.
I cleaned them with a Qtip and water. Some were more corroded than others so I reapplied more ketchup. Cleaned them again and let them all dry.
After letting them dry, I placed a ( regular ) battery in the compartments to test them. They now work !