Model 3 Battery Details

[KarenRei]

yes, supposedly the patent is different than what's in the car per the car diagram.

That diagram isn't very clear. What it appears to me is when the valve underneath "chiller" opens upward, the motor / inverter loop is connected to the cabin heating loop through "chiller". The outer loop is a glycol loop and the inner loop a refrigerant loop, and it has 4 connections, so it must involve a heat exchanger. It appears to be basically the same thing as the patent, but with things positioned differently and the "sections" not as distinct.

 

[R.S]

As per the patent diagram, the motor loop (#101) is directly connected when the valves are open to the cabin loop (#107). However, normally when you're running the motor efficiently, you've got a long wait for the motor loop to heat up. With M3 deliberately wasting as much energy as possible, the motor loop should heat up a literal order of magnitude faster.

Will be interesting to see how this effects winter range/efficiency, especially since they have to heat the stator windings, which heat up the stator iron, but also the rotor, and then the water jacket of the stator needs to capture as much of that heat as possible.

The traditional battery heater seems more efficient.

 

[sandpiper]

We know it's a new chemistry though from comments of JB and Elon. Tesla has been working on it since 2014.

There's no doubt at all that they're continuously working on various new/modified chemistries, some of which are finding their way into the cars unannounced. What's actually in this cell... only Tesla knows.

I'm looking forward to one of the hackers getting hold of one of these cells, to see what the differences really are.

 

[KarenRei]

There's no doubt at all that they're continuously working on various new/modified chemistries, some of which are finding their way into the cars unannounced. What's actually in this cell... only Tesla knows.

I'm looking forward to one of the hackers getting hold of one of these cells, to see what the differences really are.

So, basically, we're looking forward to someone getting into an accident which totals their brand new M3?

 

[cronosx]

So, basically, we're looking forward to someone getting into an accident which totals their brand new M3?

Yes.. but nothing that damage the occupant, we aren't too bad people right?

 

[Reciprocity]

Max supercharging rates are 130mi/30 min and 170mi/30 min for SR and LR, respectively. That's 59% and 55%, respectively, of the pack in half an hour, which is a bit poor performing compared to modern S and X packs when you consider that they'll never be charger-limited. It also looks like the packs may be limiting motor performance, since the 0-60 drops by half a second with the larger pack. But there could be other reasons for that. That said, regardless of chemistry differences, you should expect poorer power performance with large-format cells. Particularly with charging, since it's harder to draw the heat out. But I don't think it's a big practical difference, a lot of people were just hoping that since it's a more efficient vehicle, you'd get more miles per unit time when charging it.

My experience with owning an S/X is that I rarely see over 350Mi/h of charging and usually only for a few minutes, so if the LR is 170mi/30 and it actually is, then its easily in par with a similar ranged Model S. I will wait to complain about the charge rates until I see what they are like in the real world at a fully loaded supercharger.

 

[sandpiper]

So, basically, we're looking forward to someone getting into an accident which totals their brand new M3?

Hmmm... That doesn't sound great does it? Okay... I take it back. I hope that some brand new modules fall (gently) out of the back of a truck on the way from the gigafactory to Fremont.

 

[internalaudit]

@JeffK, if voiding of the warranty can be avoided with the heat pack (which isn't present on the 3), are Model 3 owners living in geographically frigid winter climates who have no garages screwed?

 

[Reciprocity]

So, basically, we're looking forward to someone getting into an accident which totals their brand new M3?

Just wait for one to fall off a truck under a low overpass. Its bound to happen with as many as they want to deliver.

 

[Chickenlittle]

Am concerned about components being included in battery pack. Have read about chargers going bad, soul that mean replacing the pack or increased cost of replacing charger that's inside the pack? Hopefully decreasing price of pack doesn't result in increased maintenance

 

[R.S]

Am concerned about components being included in battery pack. Have read about chargers going bad, soul that mean replacing the pack or increased cost of replacing charger that's inside the pack? Hopefully decreasing price of pack doesn't result in increased maintenance

If the pack isn't too hard to drop out, it could actually be easier to replace, than if it were built somewhere deep into the car. I'm pretty sure that the part with the electronics can be opened up more easily, than the rest of the pack.

 

[SageBrush]

Turning electricity to heat with resistive heating is 100% efficient process. So new method can't be more efficient.

Read about heat pumps. Using electricity to move heat around is a much improved idea than just turning electricity into heat.

 

[R.S]

Turning electricity to heat with resistive heating is 100% efficient process. So new method can't be more efficient.

With a heat pump you make one place colder and therefore heat something else up. So you are shifting heat from one place to another and focus it there. Resistive heating just heats something up.

So the difference between a heat pump and resistive heating is, that a heat pump only needs to overcome the entropy, but resistive heating really needs all the energy to heat up.

 

[Rogue one]

[Edit - I was assuming preheating before you start driving, but re-reading your post I’m thinking you meant that the heater would be running while driving, in which case the power train would be running anyway and using the waste heat would be pure gain.[/QUOTE]

Exactly, my post could have been worded better but I was talking about leaving with a fully cold soaked battery and the model 3 not running a pack heater vs s/x. Running a pack heater. This also makes me wonder about regen and how long it will take to gain regen without a pack heater. (Speculation). Model 3 uses regen to create heat instead of charging when the pack is cold? That would make sense to me but I don't know.

 

[chronopc]

It can if you were wasting heat before. See heat pumps.

What's the lowest temperature that the battery need to be for optimum performance?

 

[SageBrush]

What's the lowest temperature that the battery need to be for optimum performance?

The schematic says that active heating is used until the battery is 8C

 

[chronopc]

The schematic says that active heating is used until the battery is 8C

That's about 46F. It very rarely gets that colder than that where I live.

 

[apacheguy]

Am concerned about components being included in battery pack. Have read about chargers going bad, soul that mean replacing the pack or increased cost of replacing charger that's inside the pack? Hopefully decreasing price of pack doesn't result in increased maintenance

Yeah, my thought as well. Master chargers are easier to get at currently (underneath rear seats). Additionally, a pack not designed for fast swapping also means that it will take a service center longer to access it.

 

[SageBrush]

That's about 46F. It very rarely gets that colder than that where I live.

We are colder for 6 months of the year but mostly at night and the car will usually be plugged in to allow pre-conditioning before a drive.

I figure a good 10% of source battery energy gets wasted before the wheels. If Tesla can collect all that energy and direct it to where it is needed during the winter the efficiency hit from the cold may turn out to be quite minimal in most cases and even more likely during long drives where it matters most.

 

[gregincal]

That's about 46F. It very rarely gets that colder than that where I live.

That corresponds roughly to my experience in the S. When overnight lows have been lower than that, driving the car in the morning takes a lot more energy (it might already be warmer than that when I'm leaving, but the pack is still cold from the night).