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Discussion Starter #1 (Edited)
It's not DIY or even a professional conversion, but for anyone looking for inspiration for their pickup truck conversion...

Road&Track article: The 2020 Rivian R1T Electric Truck Does 0-60 in 3.0 Seconds With 400 Miles of Range
Company website: Rivian

R&T:
This Michigan-based automotive startup is swinging for the fences with a hugely innovative electric pickup truck.
No, there's nothing particularly innovative here.

Battery pack sizes:
  • 180kWh (claimed 400 miles of range)
  • 135kWh (claimed 300 miles of range)
  • 105kWh (claimed 230 miles of range)
The range claims are presumably rough round numbers, assuming ideal conditions, and fictional.

R&T:
The batteries feed an electric motor at each.
... wheel, presumably. And not in the wheel; just one per wheel. Power is listed as 200 hp per motor and 750 hp total, presumably peak. "Total grounded torque" is also listed, as 14,000 Nm; that's presumably torque to the wheels.

It is described as having a "skateboard platform", and actually almost does (the upper part of the front suspension is not attached to this structure, so it isn't quite a skateboard), unlike - for instance - a Tesla. Neither the article nor the website appears to mention the four-wheel independent suspension, multi-link in the rear; that's almost as unusual for a pickup truck as being electric, and it's actually relevant to the electric drive because the drive motors at each axle lead logically to independent suspension.

The bed floor looks really high, like a Honda Ridgeline. This is presumably to allow for the "Gear Tunnel" and rear spare tire/storage well.

The bed looks really short, and it probably is - the truck is 415 mm (16") shorter than the shortest Ford F-150, and only 140 mm (5.5") longer than the mid-sized Honda Ridgeline.
 

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Discussion Starter #2
Looking for other references led me to the press release, which I had not previously read. There are different power levels for each battery pack size. It also lists weights, which show that it is not very front-heavy: it will not handle a lot of load in the cargo bed well. It also has length dimensions for wheelbase and the cargo bed.

An amusing detail is that there is a 95 litre storage space under the seat, but not in the largest-battery version, so apparently a portion of that battery sticks up from the skateboard.

Motor Trend has some interesting mechanical details - full marks for them.
Jalopnik is the only one to catch (albeit in the reader comments) that the Gear Tunnel is an inferior version of the compartment in the original VW pickup, and similar to cars from the 1930's.
The others don't add much to the press release.
 

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Discussion Starter #4 (Edited)
Battery configuration

The battery description in the Motor Trend article (I didn't see it anywhere else):
Regardless of capacity, each battery pack is made up of modules that can be replaced individually and won't strand the vehicle if one goes down. Each module holds up to 15 kW-hr and contains 864 cylindrical 21700-type cells. The small battery uses seven modules, the midsized one has nine, and there are 12 in the MegaPack. All have been fully tested to work between -40 and 122 degrees Fahrenheit.
This is interesting, because it suggests that either:
  • the modules are all in series, meaning that the system voltage is very different between capacities and there must be a bypass for each module in case of failure; or,
  • the modules are all in parallel, with an internal configuration of something like 108s8p (assuming about 400 V nominal), and a full 108-point BMS for each module.
The capacity and cell count values imply about 17 Wh and 4.6 Ah capacity per 21700 cell, regardless of module configuration.
 

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Nice analysis Brian! It is an elegantly designed vehicle.

I’m thinking they paralleled all of the packs based on how they describe one being able to fail


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Discussion Starter #6
I’m thinking they paralleled all of the packs based on how they describe one being able to fail
It would work, and if they're configured this way a single module would be a potential short-range battery pack for a small EV.
 

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Discussion Starter #7
Still digging nuggets out of Rivian's media package...

The motor output is listed as 147 kW each (one motor per wheel) but from 300 to 562 kW limit on total input to the motors depending on battery, so the battery is always the limit on the total. Torque is 560 Nm or 1120 Nm total (to all four wheels), again depending on battery, and that gets multiplied by 12.5 to get wheel torque (i.e. a 12.5:1 reduction gearbox on each motor).

The 135 kWh battery is actually capable of higher power output than the 180 kWh battery (562 kW versus 522 kW), so something interesting is going on, such as cooling limitations. The total torque output is the same for those two sizes, so either the torque is limited by the motors, or whatever is going on with the big battery limits power more than current.

I didn't see any specification of regeneration power.
 
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