The following batteries are prohibited from being shipped in The Big Green Box:
Batteries containing free-flowing electrolyte. For example, automotive and motorcycle batteries contain a highly acidic electrolyte, which may leak from the battery if shipped within the Big Green Box.
Low production run and prototype batteries. Unless you work for a battery manufacturer or research laboratory, you probably don't have to worry about this category. Low production run and prototype batteries generally have not been put through the same rigorous testing as batteries sold to consumers, and therefore should be transported in specialized packaging.
Damaged, defective or recalled batteries. Similar to low production run and prototype batteries, the DOT is concerned that damaged, defective, or recalled batteries may pose a greater risk of harm when being shipped and should therefore be transported in specialized packaging.
If you are unsure whether your batteries fall into any of the above categories, call a customer service rep at 877-461-2345 or email firstname.lastname@example.org.