Apple iPhone chargers are not inherently unstable and only kept from bursting into flames while charging by the circuitry attached to them.
A lithium ion battery is prone to a runaway thermal reaction if you charge it or discharge it too fast or too far. [1][2] Circuitry in the charger and usually directly attached to the cells in the battery permanently break the circuit if the battery voltage or current exceeds a pre-set range.
This is not like the Keurig k-cup DRM where they are 'ensuring quality' by forcing usage of Keurig-only supplies. This is a life safety and brand protection issue that an improperly built battery can jeopardize both. The consequences are not a bad cup of coffee.
A lithium ion battery is prone to a runaway thermal reaction if you charge it or discharge it too fast or too far. [1][2] Circuitry in the charger and usually directly attached to the cells in the battery permanently break the circuit if the battery voltage or current exceeds a pre-set range.
This is not like the Keurig k-cup DRM where they are 'ensuring quality' by forcing usage of Keurig-only supplies. This is a life safety and brand protection issue that an improperly built battery can jeopardize both. The consequences are not a bad cup of coffee.
[1] https://www.youtube.com/watch?v=UaCMevegaiA
[2] https://www.youtube.com/watch?v=6M4YuMYGclM
edit: added links to youtube videos