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Some hints I have derived from public documents for the US-spec Solterra.

Battery pack is 96 cells and 72.8kWH. That's 758.3Wh/cell.

Battery pack is 96 cells and 355.2V. That's 3.7V/cell. The (likely) CATL cells are rated at 3.65-3.7V.

Rated capacity (according to the 2023 Subaru Solterra Specifications) is 201Ah. I think this wrong and is for the Panasonic pack. 205Ah at 355.2V is 72.8kWh. Now that's a bit better. 201Ah at 96 cells at 3.7V is 71.4kWh, which is the stated capacity of the FWD bZ4X pack.

I could find no public documents describing the 200-ish Ah (likely) CATL cells being used, but similar cells from them start at 50Ah and go up from there to 175AH.

They are constructed from prismatic cells, (likely) the same as the Panasonic cells.

Those cells are "8-1-1" type cells. That's 80% nickel, 10% cobalt, 10% magnesium.

Those cells have a nominal voltage of 3.7V.

The LFP cells from CATL have a nominal voltage of 3.2V.

The CATL NCM cells have a charging voltage of 4.2V and a maximum charging voltage of 4.25V.

For 96 cells if the DC fast charger supplied 400V, that would be 4.167V/cell, close to the rated charging voltage.

That explains the 355.2V-rated pack vs. the 400V DC fast charging.

Fast charge rate and max. charge rate are both 1.0C. That would generally indicate charging at a peak rate of no more than 82.7kW, definitely nowhere near the 150kW specified rate of the Panasonic cells and much closer to the 100kW specified rate of the CATL cells.

Maximum discharge for the CATL cells is specified as 2.0C, which is 145.6kW, which is close to what the two 80kW (rated) motor (likely) draw and the controllers might be limiting the draw to that 145.6kW, except maybe for brief periods.

Specified discharge (cell) temperature is rated for -20C to +60C or -4F to 140F.

Specified charging (cell) temperature is rated for 0C to +45C or 32F to 113F.

Most 8-1-1 cell charging curves show it accepting nearly no current at 0C and increasing from there.

All of this is consistent with what we have been hearing in the press releases.

Now, I would like to know why no one at Toyota or Subaru seemed to notice that the cell temp for DCFC had to be at least 32F?

I will do more research, but I think that when the 6.6kW AC charger is used, it might be able to warm the battery pack, whereas the DCFC circuitry might not be able to.

Start with the service manuals for the bZ4X on the techinfo.toyota.com site and peruse the electrical diagrams and other material if you want to figure this out. My two day subscription expired and I don't care to know the answer that much...
 

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Great info!

For 96 cells if the DC fast charger supplied 400V, that would be 4.167V/cell, close to the rated charging voltage.
That explains the 355.2V-rated pack vs. the 400V DC fast charging.
DC fast chargers can vary voltage 400-1000V as requested by the EV. 355.2V is nominal voltage.

Fast charge rate and max. charge rate are both 1.0C. That would generally indicate charging at a peak rate of no more than 82.7kW, definitely nowhere near the 150kW specified rate of the Panasonic cells and much closer to the 100kW specified rate of the CATL cells.

Maximum discharge for the CATL cells is specified as 2.0C, which is 145.6kW, which is close to what the two 80kW (rated) motor (likely) draw and the controllers might be limiting the draw to that 145.6kW, except maybe for brief periods.
1C charging is straight up garbage... super conservative. Oh wait.. Ford did that with the Mach-E. Owners were not happy with it.

2C discharge isn't great either but you rarely need 145 kW. That's hard acceleration from 0 to 85mph (I saw the ID.4 power graph where it hit 150 kW for a brief moment around 65mph).

Those cells are "8-1-1" type cells. That's 80% nickel, 10% cobalt, 10% magnesium.
Manganese not magnesium.

Specified discharge (cell) temperature is rated for -20C to +60C or -4F to 140F.

Specified charging (cell) temperature is rated for 0C to +45C or 32F to 113F.

Most 8-1-1 cell charging curves show it accepting nearly no current at 0C and increasing from there.

All of this is consistent with what we have been hearing in the press releases.

Now, I would like to know why no one at Toyota or Subaru seemed to notice that the cell temp for DCFC had to be at least 32F?

I will do more research, but I think that when the 6.6kW AC charger is used, it might be able to warm the battery pack, whereas the DCFC circuitry might not be able to.

Start with the service manuals for the bZ4X on the techinfo.toyota.com site and peruse the electrical diagrams and other material if you want to figure this out. My two day subscription expired and I don't care to know the answer that much...
Yeah, it's common to force EV owners to connect their EV to L2 to heat the battery up in sub freezing climates.
 

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Yeah, manganese. Damn, if it was magnesium, that would explain the hot battery pack fires. o_O

I was quoting the 1.0C charge rate specified by CATL, though not necessarily for the exact cells being bought from CATL by Toyota.

A 355.2V NCM pack is fast charged by a 400V DC source. Anything less than 400V and charging is slower or non-existent. Anything greater exceeds the cell manufacturer's rated specifications upon which their warranty is based.

None of that means that CATL and Toyota aren't testing and qualifying appropriate charge settings and that they won't change (improve) over time. But that's a big hope.

Still interested in a Solterra.
 

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It would be way simplier if they would only give the damn info ! I would love to have a LFP Solterra, but not sure about a slow NCM… surely someone at Subaru must know the answer ?
 

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I contacted Subaru of America in mid-May to see if they would provide additional information on the battery chemistry for the Solterra. I had a nice rep that looked into it and got back to me regularly to tell me he was in contact with Product Development and awaiting details from them. Finally, today he got back to me with an answer:

"I heard back from our Product Development. The available information on the battery for the Solterra is that it is a lithium-ion battery. Further specifications for the chemistry for the battery are proprietary."

Probably not a great sign, because if they could brag about the long life or great safety of their batteries, I would assume they would be doing it. Hopefully, Subaru will release more information or we'll get some real-world data before we need to decide whether to pull the trigger on this vehicle.
 

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I’d bet the vague answer has more to do with them keeping the flexibility to alter the definition of the product (batteries and/or vehicle) combined with protecting the selection of suppliers and the specifics of their products. I used to have to make similar statements about products, processes, and suppliers.
 

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crazy to buy a car that price and can't even have basic information on what you are buying... we will have to wait for a teardown...
Here in Europe we need probably 50k€ or 60k€ to buy one of these cars and you can't even know what technology they use and how long they can last.
If I spent 60k€ I am not only keen to know the chemistry of the battery but also how do they perform in a charging-discharging test? How long can they last? How many cycles in average? I am not going to buy a Blackbox even if with warranty
 
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