But a lifetime of 3y doesn't jive with why my 7 year old vehicle is mostly fully functional. Even with 10% over-provisioning (amazingly expensive 7y ago), that's only a 15% reduction in 7 years.
The statement "The life of the commonly used chemistries is only around 3 years" is completely misleading and probably inaccurate.
I don't know about the 3 years number, but generally speaking battery lives are estimates/averages based on statistics. If you have a battery that was well cared for it will outperform the average. Also sometimes it's just dumb luck. One aberration isn't nearly enough data to throw out the entire premise
The statement "The life of the commonly used chemistries is only around 3 years" is completely misleading and probably inaccurate.