Re: Battery Capacity
It can be 50% after 18months. It's number of cycles and temperature. A sealed in battery will not meet SOGA requirements for all customers.
An eInk Kindle or Kobo may use same sealed in LiPoly cell as a phone, but charge cycle can be week to a month vs daily for a smart phone with unlimited or high data cap. If your signal is poor and you use WiFi and and BT on all day then you may charge when you get home and again going to bed, and some users will only see 1 year battery life. But an eInk reader with same cell might last 5 years or more. Screens get broken.
I use my ancient Soiny Z1 with WiFI off, BT off and only about 1 or two calls a week, so I often only charge once or twice a week hence replaceable battery is ironically fine and nearly four years old? (The original).
My Inspiron 8200 was used from 2002 to 2016, so no surprise it's on fifth battery pack, it's on 3rd keyboard and I replaced case once by buying a scrap compatible model.
You can buy replacement NEW casings for 2 way mobile radios. Quite old models. Also Yaesu is very good for replacement parts for Amateur and Vertex Radio gear.
Most consumer Electronics companies don't want stuff to be repairable. There is also the issue that a new TV or BD player is cheaper than a repair. Repairs need to be subsidized to reduce scrapage, so called recycling. But most expert repair people have retired. Most places you'll only get a screen on popular phones replaced. Forget eInk or anything uncommon.
Fridges and microwaves are rarely fixed, even though they are very repairable. The parts are too dear and to pay proper technician with training, tools, insurance etc is more expensive than a new one. Forget kettles, coffee machines, toasters. Unless you learnt all this stuff 40 years ago and have an attic full of stuff you never threw out to cannibalise for parts.
So this is worthy, but we need something more radical to have real repair and reuse rather than so-called recycling, were much isn't. Though car batteries are a success. It would be even better if the case was re-usable. They currently are not.