How can I punish bad sellers on AliExpress?

Did you pay with PayPal? Credit/Debit card? Disputes and charge backs are usually the only thing you can do post sale. I assume that if you were to start a dispute with Ali, they would want you to ship it back. Cost more than the battery most likely. Use the help of whatever method you chose. You won’t keep everyone from buying them but they won’t get your money for a less than stellar product.