That has a) nothing to do with the topic at hand (improving recycling rates) anr b) isn't even effective. A deposit isn't a tax. You need to give the consumer money for actually bringing the product to a recycling spot, so a tax doesn't help. Psychological it's a better motivator if that money was originally paid by the consumer as in you're losing money you paid, if you don't bring it back, and it's also much easier to implement.

If you want to tax non-replaceable batteries that will just be factored into the price and the thing is that easily replaceable batteries are in conflict with other design goals consumers are willing to pay for (like water proofness).

I understand the frustration with non-replaceable batteries creating some kind of planned obsolescence, but there is no easy solution without sacrificing other things.