This second part confirms that updates to iOS were responsible for the CPU throttling, which was an effort to
reduce bursts of power usage (like you would see when running a benchmark app), and is what caused the low scores that Reddit users and Primate Labs described when testing older phones.
Paired with ultracapacitors, batteries wouldn't need to deliver
bursts of power and so could be made with just a few layers
of very thick electrodes,
reducing the amount
of supporting material needed.