alozzy wrote:FWIW, if you take the data from table 2 and assume that 100% DoD is equivalent to 80 miles (range of a new 24 kWh Leaf), then below are the number of miles one could travel until the battery degraded by 30% of its original capacity:
- 100% DoD cycling - 48,000 miles (600 cycles x 80 x 100%)
- 80% DoD cycling - 57,600 miles
- 60% DoD cycling - 72,000 miles
- 40% DoD cycling - 96,000 miles (3000 cycles x 80 x 40%)
- 20% DoD cycling - 144,000 miles
- 10% DoD cycling - 120,000 miles
Obviously, the range diminishes as the battery degrades but the numbers above are really just for relative comparison. Interesting that when comparing 40% DoD cycling to 100% cycling, the miles travelled doubles.
If you believe that source, then daily charging based on a 50% DoD cycle should result in a loss of 30% capacity after roughly 85K miles. These numbers seem too pessimistic to me, since I'm guessing my Leaf will have gone 120K miles by the time the SOH drops to 70% - I don't think I've averaged roughly 30% DoD charging cycles, it would likely be more like 50% DoD on average...
Perhaps the data was based on testing at hotter temperatures, with no TMS. Or it's just a bunch of BS
the cycling chart is not valid unless a "heat" factor is applied. The issue we have (that most here seem to ignore) is that there is a degradation curve that varies with temperature and that curve starts at a shockingly low temperature.
The other question is what 40% DoD means? Is that 40-80% SOC? Because if it is, that only means that issues with heat are magnified.
Finally I love Battery U for the legwork they have done but they have only recently started concentrating on the specific issues EVs face. So a realistic picture requires stitching several studies together with leaps of logic to make sense of them.
This last part is something that most refuse to accept.