SageBrush said:
WetEV said:
The LEAF v1, with only 35 miles of "No Worries Range", was a niche car. You had to fit the profile for the car to work for you: a commute not too long, not to short, not too cold, not too hot, have a second car and so on. Many of the early buyers didn't fit the profile. So they were unhappy.
You are rewriting history again.
The owners became unhappy when their 35 mile "No worries Range" car dropped to 25 miles
Mostly in hot places, at first. Some outside that as well. Yes, Nissan's first production battery was a dud. BTW: You misunderstand "No Worries Range". That includes at least a 30% drop in battery capacity. Not many LEAFs had a 30% loss then a second 30% loss. A few have since then, by missing the warranty or being in a really hot place, but not that many.
There were some in the Seattle area that had 50-60 mile commutes. These became challenging, at minimum, even before the battery had lost much range, as they were beyond the "No Worries Range".
Back on topic, active cooling, or lack of, wasn't the real problem. Nissan would have had almost as large of a problem with an alternative LEAF with active cooling. As did Ford, with the tiny volume FFE. Look at the test results comparing FFE and LEAF in AZ. The problems were chemistry and use, not active cooling.
As chemistry isn't a simple thing, and even knowing people that claim to understand battery chemistry... I'm not convinced that they do. However, active cooling sounds simple, so that's what gets the blame. Yet battery cooling isn't the panacea that many think it is.
Hotter places will still have faster capacity losses. They will also see the most gain from battery cooling, along with the largest energy draw for cooling.
Average places will still have faster capacity losses. They will see both little gain from battery cooling, and little energy draw from cooling.
Cool places may have faster capacity loss with active battery cooling, and will see almost no energy draw from cooling. The faster capacity loss is due to design of pack having less passive cooling. This is likely necessary to minimize energy draw in hot places. Complex subject, probably matters little.
What can an active cooling system do? Mostly limit the peak pack temperature to something like 40 C to 45 C or so. Can't cool much below that without taking a risk of condensation, which is deadly for electronics and batteries.
So, in a cool place, would an active cooling system do anything at all? Not in my experience, as I've never gotten over 38 C battery temperature ever, and that only once, in summer, on a long trip with multiple quick charges.
So in Denver (or San Jose), would an active cooling system do anything at all? Denver is about 5C warmer than Seattle. So if you drive like me, maybe limit temperature a few days per year by a few degrees, with a 40 C threshold. This might improve battery lifetime by a few days over years. Basically, nothing. And nothing at all with a 45 C threshold, as Tesla uses.
How about Phoenix? Average temperature is 15C warmer than Seattle. Battery with just commuting might average 35 C in July, with or without active cooling. More, if you need to park in a sunny parking lot. With long drives, spirited driving, and multiple QCs, you could easily cook a passively cooled battery. Here is the case for active cooling, not Denver and really really not Seattle. You might do OK with a lizard battery in Phoenix, if you just commute, have covered parking during the day most of the time, and a cooler place to park and charge at night.
If I was to rewrite history, I'd have Nissan wait a few years to bring out the LEAF with reasonable battery chemistry, and market it in Phoenix with warnings about keeping the car from getting too hot.