That is right, HAs are usually replaced completely- if the model still exists. A recent breakdown of the costs of HAs set the material (parts) value at a few hundred dollars, so the labour costs of repairs quickly exceed those. Yes, you could choose HAs with disposable batteries, but the current manufacturing trend goes against this. Given the limited lifespan of lithium batteries I rather see two solutions; first, why can’t those lithium accus be placed in an easily accessible compartment, just like for standard batteries? The EU is enforcing legislation that obliges electronics to carry lithium batteries that can easily be replaced, and this will likely also be the new global standard. Second, giving the shift to streaming (Bluetooth/TV streamers), why not increase the size/capacity of those rechargeables, so they comfortably last an entire day however you use your HAs? Most users aren’t vanity idiots who care about tiny, “invisible” HAs.