That EE video for one thing, only looks/references a single report and another thing is mixing up calendar aging and cyclic aging.
That report, just as most of the things I see people reference to from Jeff Dahn is about cycles.
We need to get one thing straight:
-we will not kill our LFP batteries from cycling them when using the car.
They can litterally do several thousands of 100-0% cycles.
So *any* discussion about how to cycle them from a cyclic aging perspective is going on a hunt on an issue that simply does not exist.
The cyclic aging will be almost undetectable or close to this anyway.
This is only one of several tests showing how little cycles wear on LFP.
The chart shows how many EFC (equivalent full cycles) we get before we have lost 20% (80% remaining capacity).
Just look to the right and compare with NMC and NCA.
Regardless of how we cycle the LFP's we seems to get 3000 FCE. One FCE is driving from 100% until the car stops. This would probably give us at least 300km or 200 mile on a 3 or Y RWD.
3000 x 300 ? 900K km, for 20% loss. This equals about 0.2% per 10K km or 0.4% annual for most drivers. This was when using the worst case scenario of the tested. Most people will do smaller cycles and the curerent rate is not above C/2 (more like C/3-3.5). So we probably are looking at something more like the 20-80 chart with 6000+ FCE....then the annual cyclic aging would be ~0.2% for the average driver.
Hunting cyclic aging on LFP is hunting ghosts.
So we need to focus on calendar aging if we would like to reduce the degradation (which there isn’t any need to, but it is possible).
Calendar aging is reduced by timing charging so the car does not spend a lot of time between 72-100%, where 75-90% probably is as “bad” as 100% or worse.
Maximizing the time the pack spends at 70% or below will reduce the cyclic aging noticable (if the car manages to see the saved capacity is still to be determined).
Charging late, with 11kW AC and driving shortly after the charge is finished does not cause much calendar aging. In the big picture it is not noticable.
