So for a decade we've been told that active battery management of lithium batteries is good. Lithium batteries (for their longevity) like to stay around the same temperature as humans, 20C. Nissan don't have liquid cooling and suffer range loss in hot states (Arizona where some lost 30% range in 1-2 years, and chargegate where they can't cool the battery). Monitoring tech showed temperatures of 45-55C and charging speed curtailed to prevent overheating.
But crazily we now see in a newish Bjorn Nyland video like below that Tesla is actually using 9kW of "heaters" to heat the battery to an insane 50-55C while the car is stationary, sat supercharging!! Not just at the start, but 10-15minutes into the session! The battery is approaching 50C and the heaters are still heating it more and more! Wasting massive amounts of energy imho.
It "has" to be detrimental to the life to heat it that much!
So - just to be clear, this is not a battery being left to heat up to 50C by the process of charging. That would be okish. The car is actually "diverting" an extra 9kW (4.5kW per drivetrain) of power on top of the 120+kW from first the battery (while approaching the charger), then at the supercharger to the motor stator(s) to heat the battery long into the charge session. So Bjorn has an OBD tool monitoring 100+ sensors - and it's right there in the display. 4.5kW energy used per drivetrain! Bjorn is even aware of it, calls them the preheat "afterburners". That Tesla run the motors inefficiently to overheat the stators and run the coolant loop as heaters.
I'm amazed this isn't a bigger environmental scandal from a company that "claims" to be the best course for us to prevent waste, global warming, and clean energy, but here we have a massive 9kW of electricity (enough to run 9 average European houses - 1kW is average for Europe, 2kW for the US) just being used to speed the charge time up by a few minutes! This is not an insignificant "waste". This is 9kW per supercharger, and there's 15,000. Of course the second the car leaves the supercharger it's then wasting more energy to actively cool the battery it just cooked! The coolant flow rises to max speed, the inflow temp drops to about 10C below the battery temp and it tries to now cool the battery, 30minutes later the battery is back to circa 25C.
So this is 9kW just to heat the battery - not chemical energy of electrons for more miles - this is just "thermal" energy dumped to the atmosphere from a heater, then re-dumped by the radiator (coolant).
Now recall this is Tesla. When Elon lectures us about global warming, heating the planet, the need to go solar, wasting energy, etc. So is this technical solution not slightly ironic for a company claiming to be all about efficiency and preventing waste? I recall the slogan of Google. "Don't be evil". Tesla's motto is about fun, but also energy efficiency. I think this is a massive violation of. It's like Greenpeace leaving patio heaters on outside their offices!
I imagine the batteries at 50C can charge quicker than at 20 or 30C - but heating to 50C then cooling them to 20C is such a waste of energy!
First I don't think Tesla should do this - it's a bit "evil" in the Google thinking.
Secondly, charging a battery heats it anyway, don't heat it to 50-55C with a 9kW heater as well. This is insane.
I'd like a setting not to heat the battery - I might not be in a rush. It's wasteful at best, evil at worst. Don't be evil !!
For more on the OBD variables (battery temp, coolant inflow, outflow, stator front / rear) and 100+ others, there's also this video.
See video here regarding OBD -
But crazily we now see in a newish Bjorn Nyland video like below that Tesla is actually using 9kW of "heaters" to heat the battery to an insane 50-55C while the car is stationary, sat supercharging!! Not just at the start, but 10-15minutes into the session! The battery is approaching 50C and the heaters are still heating it more and more! Wasting massive amounts of energy imho.
It "has" to be detrimental to the life to heat it that much!
I'm amazed this isn't a bigger environmental scandal from a company that "claims" to be the best course for us to prevent waste, global warming, and clean energy, but here we have a massive 9kW of electricity (enough to run 9 average European houses - 1kW is average for Europe, 2kW for the US) just being used to speed the charge time up by a few minutes! This is not an insignificant "waste". This is 9kW per supercharger, and there's 15,000. Of course the second the car leaves the supercharger it's then wasting more energy to actively cool the battery it just cooked! The coolant flow rises to max speed, the inflow temp drops to about 10C below the battery temp and it tries to now cool the battery, 30minutes later the battery is back to circa 25C.
So this is 9kW just to heat the battery - not chemical energy of electrons for more miles - this is just "thermal" energy dumped to the atmosphere from a heater, then re-dumped by the radiator (coolant).
Now recall this is Tesla. When Elon lectures us about global warming, heating the planet, the need to go solar, wasting energy, etc. So is this technical solution not slightly ironic for a company claiming to be all about efficiency and preventing waste? I recall the slogan of Google. "Don't be evil". Tesla's motto is about fun, but also energy efficiency. I think this is a massive violation of. It's like Greenpeace leaving patio heaters on outside their offices!
I imagine the batteries at 50C can charge quicker than at 20 or 30C - but heating to 50C then cooling them to 20C is such a waste of energy!
First I don't think Tesla should do this - it's a bit "evil" in the Google thinking.
Secondly, charging a battery heats it anyway, don't heat it to 50-55C with a 9kW heater as well. This is insane.
I'd like a setting not to heat the battery - I might not be in a rush. It's wasteful at best, evil at worst. Don't be evil !!
For more on the OBD variables (battery temp, coolant inflow, outflow, stator front / rear) and 100+ others, there's also this video.
See video here regarding OBD -
Last edited: