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2023 i4 m50 Portimao/Oyster
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Hmmm...

BorgWarner’s heater tech used in BMW iX and i4

and...

The basic thermal management (i.e. not just cooling but also heating) for the battery and associated hardware comprises three coolant circuits, interconnected by electric valves, all of which share a common expansion tank. This can, for example, allow heat from the drive motor to warm the battery pack. The new heat pump system uses 75% less energy than the current i3 and consists of a high-voltage refrigerant compressor, a pair of evaporators, a water-cooled condenser, and two 9KW heaters for extremely cold conditions. Surprisingly, the resultant energy savings can increase driving range by up to 30%. While the advantages offered by enhanced battery density, less weight and a more efficient drive unit benefit handling and acceleration, BMW has also considered that EVs tend to have feeble towing capacities. Yet, the i4 can tow up to 1,000 kgs.
From: New Car Focus: BMW i4 - autotechnician - servicing the independent workshop
 

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Hello SSH - While it certainly could have 18 kw heater's it sure sounds excessive. Most all these chatter type reviews are guys just reading from the same press release. Unless data comes from BMW or a technical institute where they disassemble the car, they hold little credibility.

I can't think of a heating protocol that would require or need to heat the battery that quickly. The I4's winter driving heat cycle used prior to charging could easily use a 6-8 kw heater by simply starting the heat cycle sooner producing the same results when the user reached the charge destination. The added benefits of a smaller heater would be less cost and less weight for added range.

Regards - Mike
 

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In a discussion with some guys in a I pace group a year or so ago, I figured to heat my I-pace battery from 32 to 77 degrees for opium charging speed, using a 15 kw element heater, would take 52 miles from the cars range. So if the charging station was 60 miles away it would require the car to have 112 miles of range to make it there. While I can't recall exactly BMW resigned their GEN 5 batteries to be at their highest capacity I think around 90 degrees instead of 65-70 degrees of the BMW I3 batteries.

Regards - Mike
 

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i4m50, 18inch 245/255 summer 18 inch 245/245 winter, order aug 21 - Delivery next week?
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Some testing in the iX 40 (Small battery approx 75KWH).
between -5 and zero celsius.
Adding Charger to route, 5 minutes before arriving - very slow charging - 30 - 35 KW.
Adding Charger to route, 10 minutes before arriving - Fast charging 140 - 150 KW - (ix 40 - has max charging of 150)

Both of them after driving more than an hour at temperatures between -5 and zero.
 

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2023 i4 m50 Portimao/Oyster
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Hello SSH - While it certainly could have 18 kw heater's it sure sounds excessive. Most all these chatter type reviews are guys just reading from the same press release. Unless data comes from BMW or a technical institute where they disassemble the car, they hold little credibility.

I can't think of a heating protocol that would require or need to heat the battery that quickly. The I4's winter driving heat cycle used prior to charging could easily use a 6-8 kw heater by simply starting the heat cycle sooner producing the same results when the user reached the charge destination. The added benefits of a smaller heater would be less cost and less weight for added range.

Regards - Mike
The 9kW chargers are for the cabin, I believe, as well as the battery. I can tell you it will heat the car to a comfortable temperature from -10ºF in the 30 minute preconditioning window. I love it!
 
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