Stoaty said:
planet4ever said:
If so, RegGuheert's numbers would suggest that 6 bars in a new battery is really about 50F-73F.
Common sense tells me this can't possibly be so. My parking garage generally runs 60-70 degrees F. I almost always see 5 temperature bars when Leaf has been in garage for a period of time. Yesterday, my Leaf had 5 temperature bars, garage temp about 70 degrees F. I took it out for a few errands (ambient temp outside was 75 degrees in the shade) and in about 30 minutes it showed 6 temperature bars). My battery has about 6% capacity loss. Temperature bar changing to 6 right at the expected junction (74 degrees F.)
I can certainly see your point, but common sense also says that your interpretation of the original table can't be possible. If 74°F is the
minimum for 6 bars, then 5°F is the minimum for 0 bars, meaning that you would not be allowed to start the car if it had been sitting outside for some time at zero degrees. That hardly seems likely. On the other hand, if 74°F is the
maximum for 6 bars, then you lose the last bar at 5°F, and 140°F is the maximum for 12 bars, meaning that you would not be allowed to start the car if the battery temperature was 140°. This makes lots of sense.
OK, so we have two interpretations, and neither of them seem to be possible. Please note that my statement started "If so," and the condition was that the transition points start at the low end of the ranges shown in the graph, and move upward as the battery ages. The only justification I have seen for that is that the first edition table Nissan removed showed that happening. So let's think some more about this:
dgpcolorado said:
What I don't get is why Nissan changes the temperature scale as the battery degrades?
Why indeed? Could it be that a degraded battery becomes less sensitive to heat, so can be run hotter without further damage? If so, they could raise the bars, on the assumption that we would be thinking "6 bars is OK, 7 not so good." But, help me out here, some of you battery chemists, I wonder if a degraded battery might not become even more sensitive to heat, so the Nissan engineers would want to warn us earlier by lowering the transition points. If the transition points actually start at the high end of the ranges, then 5 bars in a new battery would go up to 81°F and Stoaty's observations with a slightly degraded battery could be right on.
It's the wrong time of the year to ask this, unless we have a reader in southern Chile, or possibly (if it gets colder than I think) in the mountains southwest of Canberra, but have any of you cold weather folks tracked your battery temperature bars against the car's temperature during the winter? Do you really see 2 bars if the car sits outside starting at about 10°F (-12°C), or does it have to be more like 28°F (-2°C)? Have you ever tried to start the car after it had been sitting at less than 5°F (-15°C)?
Ray