[pasei]

I noticed something interesting today. It's 50°F and sunny in Boston (this January has been nothing short of insane). After driving 12 miles with the cabin at 70°F, I did a change of interstate, so the battery charged to 100% when I slowed down and then depleted almost entirely when accelerating on the other interstate. Then the HV battery fan went into TURBO mode. It's the first time I hear it in in 2000 miles. It lasted about 5 minutes. So conclusions/ questions:

- I guess the fan has a variable speed, didn't know that. Do we know the kick in temperature?
- Seems like 50° outside/ 70° inside is enough to "overheat" the battery pack. Does that mean the maximum efficiency of the car is reached under these conditions? People usually say that 70° is the best for batteries, but I wonder if 70° outdoor +driving would make the car past it's peak efficiency?

 

[insightfully]

Then the HV battery fan went into TURBO mode. It's the first time I hear it in in 2000 miles. It lasted about 5 minutes. So conclusions/ questions:

• I guess the fan has a variable speed, didn't know that. Do we know the kick in temperature?
• Seems like 50° outside/ 70° inside is enough to "overheat" the battery pack. Does that mean the maximum efficiency of the car is reached under these conditions? People usually say that 70° is the best for batteries, but I wonder if 70° outdoor +driving would make the car past it's peak efficiency?

From what I've read, 59-95F (15-35C) is the ideal operating temperature for short term performance and long term battery health.

Gen3 info is limited, but on the Gen1, there's mention of an inlet temperature sensor and the following operating ranges: - Better IMA battery fan - the Hybrid ReVolt way

• battery pack at 45F to 80F = fan mainly off; runs on low a few seconds every couple minutes to update temp readings
• battery pack <45F = inlet is warmer than pack; runs fan slowly to help warm pack
• battery pack >80F = inlet is cooler than pack; runs fan at varying speed according to cooling required
• battery pack >120F = fan on at full speed regardless of inlet temp

I haven't heard the HV battery cooling fan run in an alarming way in current (cooler) conditions or in hot summer conditions. Was your cabin any warmer than 80F?

 

[pasei]

From what I've read, 59-95F (15-35C) is the ideal operating temperature for short term performance and long term battery health.

Gen3 info is limited, but on the Gen1, there's mention of an inlet temperature sensor and the following operating ranges: - Better IMA battery fan - the Hybrid ReVolt way

• battery pack at 45F to 80F = fan mainly off; runs on low a few seconds every couple minutes to update temp readings
• battery pack <45F = inlet is warmer than pack; runs fan slowly to help warm pack
• battery pack >80F = inlet is cooler than pack; runs fan at varying speed according to cooling required
• battery pack >120F = fan on at full speed regardless of inlet temp

I haven't heard the HV battery cooling fan run in an alarming way in current (cooler) conditions or in hot summer conditions. Was your cabin any warmer than 80F?

Interesting! No, in fact I had turned off the heater that was set at 70°F 5 minutes before it happened. I was thinking it was from the battery going from 2 to 10 back to 2 bars in a short amount of time.