Unfortunately, batteries are not regulated by the FDA. The only regulation that I'm aware of in regard to lithium batteries is the Dangerous Goods Act, which only requires that batteries be specially labelled and packaged so that there's no chance of activation or shorting, and that falls under the Department of Transportation as far as I know.
There are no regulations that specifically deal with the relabelling of batteries, at least as far as I'm aware. This is where legislation is needed though because those who don't know any better will find themselves buying batteries rated at 30 amps when they're actually 15 and they'll end up hurting themselves. However, just like the incidents where children ended up killing themselves by ingesting nicotine, it's probably going to take quite a few more accidents to move the Government to do anything at all in that regard. I find it rather amusing that when companies put other people in danger, our Government does nothing, but when a couple kids swallow Nicotine, they suddenly start over-regulating.
Perhaps I'd better keep my big mouth shut, or the sale of Lithium batteries will be banned altogether, LOL!