Interesting. The biggest issue I would imagine is getting people to understand where and how to dispose of their electronics waste. While dedicated waste streams are likely more unit efficient, throwing away Li batteries is an infrequent enough event for most people that they probably won’t think of it or remember when the need arises. It would be interesting to see if it was possible to identify and separate Lithium batteries from general single stream waste or recycling.
"Disposable" lithium batteries are increasingly common. Mostly vapes and single-use phone charge packs. Even though these use rechargeable cells, they often don't include a means to recharge them, so people just chuck them in the bin
I wouldn't trust any German recycling claim. They've been caught multiple times selling their "recycled materials" to shell companies and illegally trucking them into Poland to be dumped on public lands or set on fire in "storage facilities".