Gary,
It's watt-hours, not amp-hours. There is a separate amp-hour calculation.
Because you aren't watching SOC, but watt-hours, expect it to go down over time as the battery ages.
-Phil
This is indeed a curious observation that the upper gids are used up faster. If you look at the graphs early in this thread, it is clear that (at least during charging), the unit value of 1 gid in wh is pretty consistent over the entire range (ignoring the noise, the graphs are very linear). Data doesn't support the observation of gids being less energy at the top of the scale.garygid wrote: If the Gids are essentially 80 watt-hours each, why are the top 20 or so "always" used up so much quicker than those in the center of the range?
Nissan seems to be confident on the durability of the batteries.. hopefully they dont pull a Honda and reprogram the limits after 3 years to reduce battery degradation.lukati wrote: For me the important information coming from Phil's data is the fact that the BMS protects only 2% capacity at the bottom and ~5% at the top. Unlike the Prius NiMH battery that Toyota won't let you abuse, your use pattern on the LEAF will truly affect the longevity of the pack. We knew that going in, now we have the numbers to prove it.
The 5% at the top doesn't surprise me, but I am stunned by the 2% at the bottom. These numbers just reinforce that I want to continue using the middle 60% most of the time for maximum battery longevity. Of course, we won't know exactly how much difference the usage pattern makes for a few years until Leafs start dropping like, well, Leafs.lukati wrote:For me the important information coming from Phil's data is the fact that the BMS protects only 2% capacity at the bottom and ~5% at the top. Unlike the Prius NiMH battery that Toyota won't let you abuse, your use pattern on the LEAF will truly affect the longevity of the pack. We knew that going in, now we have the numbers to prove it.
what varies by temperature? i am getting same "conflict" so have been tracking when i lose bars, the temp (via dash) and GID reading. it does have some drift to it. despite having a few days in the 50's its still a bit early to expect that on a regular basis but will see if numbers drift from temp changes.More typical is 18-21.5-ish kWh, depending largely on temperature. For example, I drive 100 miles, and average 4.8 miles/kWh, that infers 100/4.8=20.8kWh.
i see lower GIDs restored quicker but attribute a lot of that to less accuracy reading GIDs when pack is low and also less accuracy when pack is high. look at it like an analog gas gauge when the needle moves slowly when full or near empty and quickly in the middle. it should move at the same rate all the way thru when driving constantly? i frequently will gain GIDs when parking, sometimes as much as 9. the biggest gain did happen during a time of rapid temperature rise due to transitioning from cloudy morning to full Sun in afternoon.There is some non-linearity, true, but it's still a lot better than the 12 bars on the dash. The graph below shows the non-linearity better, I think. I plotted the energy into the battery versus time and gids vs time during the same 100% charge. You can see that the energy into the battery is a very linear constant rate (as expected), but the gids do vary a little - particularly at the low end.
the only thing we really know is what the car tells us so its battery bars, temp bars efficiency gauge and odometer.But back to the topic of gids. If I recall correctly, we started discussing it last summer, and the thread carried over to this year. My original suggestion was 75 Wh per gid, which was pretty speculative at the time. If a gid really was 80 Wh, then we might have overestimated the amount of energy left in the battery after turtle. Evnow did couple of really nice plots and this table for usable battery capacity. TickTock presented very interesting plots as well, I will try to find and link to them.