Many "dead" batteries are just heavily sulfated. Using a smart charger with a "repair" or "desulfation" mode can sometimes bring them back to 80-90% health.
Facebook Marketplace is the king for this. Always include a photo of the multimeter reading to prove it’s good. B. Selling for Scrap (The Volume Path) Target: Scrap yards or auto parts stores.
Check Facebook Marketplace, Craigslist, or Nextdoor for "parting out" posts or people cleaning out garages. Many will give them away just to have them hauled off. buy and sell car batteries
Small local garages often have piles of "core" batteries. While they usually have a contract with a recycler, they might sell them to you for a few dollars above the scrap rate if you buy in bulk. Auction Sites: Look for "lot" sales of automotive parts. 2. Testing and Refurbishing
Use a battery load tester to see if it holds voltage under stress. If it drops below 9V during a 10-second crank test, it’s likely bad. Many "dead" batteries are just heavily sulfated
To make a profit, you need to source batteries at little to no cost or buy used ones that still have life left.
People on a budget, DIYers, or those with "beater" cars. Always include a photo of the multimeter reading
They pay cash by weight. Prices fluctuate based on the global market price of lead. This is the best option for batteries that are physically damaged or won't hold a charge. 4. Safety and Legal Basics