Agreed. In which case, the parent just needs to say, “No, we do not chew on batteries, they are dangerous.” And lock them up tightly and doing whatever necessary to ensure the child has absolutely no access to them.

Sure - the child will be upset, but that’s part of parenting. It will be running with scissors next week. This parent might as well come back with questions on how to rubberize the scissors rather than prevent the behavior. Putting your foot down is just necessary.