2022 Tesla Model Y 4680

Tesla Model Y

We are gradually piecing together the data around the 2022 Tesla Model Y 4680 battery pack.

If you have test data, images, references or other data on this battery then please do send through so that we can build a better overall set of referenced material.

nigel@batterydesign.net

Caution: This is a very difficult pack to reconcile the numbers around at the moment and so we are continually updating our calculations and estimates. We will get there, but it might take some time.

Specifications:

Assuming the 4680 cell from the Munro teardown is correct at 23.35Ah then we have the following parameters:

  • total energy = 71.5kWh
  • usable energy = 67.5 kWh [1]
    • Usable SoC = 94.4%

Assuming the cell can match the energy density of a 5Ah 21700:

  • total energy = 81.2kWh (long range version)
  • usable energy = 75.9 kWh
    • Usable SoC = 93.5%

There is little real data on this vehicle and hence a number of parameters are estimated. Including the usable energy, several users have estimated this based on energy delivered during charging.

The total energy is based on the total number of cells = 828 and the cell energy = 98.05Wh and hence 828 x 98.05 = 81,185Wh. Or at 86.5Wh the total pack energy is 828 x 86.5 = 71,622Wh.

  • peak discharge power 227kW10s [1] and kW1s at %
  • continuous power
  • nominal voltage = 340V
  • voltage range = 386V to 230V

This assumes operation to the cell maximum and minimum voltage range of 4.2V to 2.5V

  • weight = 445kg
    • cells = 294kg

The difference between a Model Y with 4680 cells and a Model Y with 2170 cells is 9.1kg (20lb) as demonstrated by The Kilowatts who bought one of each type and then weighed them [3].

Tesla Model Y 4680 battery pack weight estimate

Munro weighed the battery, seats, carpets and centre console as a unit. This weighed 1198lb.

The table to the left shows an estimated breakdown to give a total battery pack weight of 445kg. Compared to a Tesla Model 3 battery pack weight of 481kg.

Tesla Model Y front seat structure

The front seat structure that lifts the height of the Model Y seats to give you the SUV driving position is substantial [5].

The cross beams and the seat raisers add up to an estimated 18.8kg

  • volume pack = litres
  • pack dimensions [m] =
    • module =
  • number of cells = 828
    • 92s
    • 9p

We need to further understand why Tesla have reduced the system voltage on this vehicle by 16.8V, the Model 3 21700 pack is 96s and that has been consistent on their previous pack designs.

  • Busbars
    • Plating – one side only, for cost and cycle time reduction, plated on the face that gets welded to the cell
    • Flatness – a big cost reduction comes from the lower overall required flatness of the busbar. Previous tolerances were much lower, because of they way the welding robots worked. Now, with new systems in place, the busbars don’t need to achieve these flatness and profile tolerances. A whole array of QC vision systems, rework stations (flattening re-presses), and protective packaging are now eliminated
Tesla Model Y 4680 9p busbar
9p busbar picked out [4]

Looking at the busbars in more detail and you can see that they are the same busbar design used for each P-group of cells, but that they are flipped over. In fact they are not the same part as the busbars are plated on the face that interfaces with the cell.

2022 Tesla Model Y 4680 battery busbars
P-group busbars in the 4680 battery pack. Munro Live [4]

In close up you can see the the busbars are narrower for those sections that join the cells in parallel compared to the width where they join cells in series. Another cost and weight reduction.

Tesla Model Y 4680 Busbar
The smaller cross-section busbars (circled in red) just join the cells in parallel and see much smaller currents. Munro Live [4]
  • charge time = ~30minutes to 80%
  • cell format = cylindrical 4680
  • modules
    • pack built from 4 large modules that run the full length of the pack
    • 107 cells in each module
Tesla Model Y 4680 cells single sided busbars

The Munro teardown video shows the single sided busbars are aluminium.

The central positive tab on the cell is aluminium and the cell can is ~0.5 to 0.6mm thick nickel plated steel.

  • cooling system
Tesla 4680 battery cooling

Serpentine coolant plates that flow water glycol and cool one side of the cells.

Note that the inlet and outlet connections appear to be at just one end of the pack. This contra flow is likely to help reduce the temperature delta that would be observed over this length.

The number of coolant connections inside the battery pack is a concern.

  • cell make and model
  • pack cost =

Key Pack Metrics:

Based on cell data from Munro teardown vehicle:

  • Pack = 161Wh/kg
    • Cell = 244Wh/kg

Assuming energy density matches the 21700 we have:

These numbers give us problems as the cell out of the Munro teardown has a capacity of only 23.35Ah and an energy density of just 244Wh/kg. This would drop the pack energy density to just 161Wh/kg at pack level.

  • Volumetric energy density, pack = Wh/litre
  • Gravimetric power density, pack = W/kg10s
  • Volumetric power density, pack = W/litre10s
  • Estimated cost = $/kWh
  • Cell to Pack mass ratio = 66%
  • Cell to Pack volume ratio

Other key features:

  • Safety
  • BMS
  • HV Distribution
  • HV and LV Connections
  • Cooling Connections
  • Structural pack
Tesla Model Y body and structural 4680 pack

The Tesla Model Y has a structural battery pack. There is a body side beam running across the top of the pack where the rear heal board goes. There is also east-west structure for the front seats. However, this doesn’t tie-into the sills.

Although note that in this mockup [5] it shows the cooling plates running east-west. We know from the Munro Live teardown that the cooling runs north-south.

  • Case material
  • Sealing strategy
  • Venting strategy
Tesla Model Y 4680 battery pack

Cells vent downwards with a mica sheet underneath. See the Munro video link in the references for more details.

At this point it is not clear how venting gases are dispersed under the cells and then allowed to exit the pack.

  • Durability
  • Availability
  • Recycling
  • Shipping

References

  1. Tesla Model Y with new 4680 cells shows impressive potential for faster charging – Electrek
  2. 4680 Battery Pack: What We Found Under the Foam! – Munro
  3. What Difference In Weight Do Tesla 4680 Cells Make? – TorqueNews
  4. Tesla’s 4680 Current Collector Layout – Munro Live
  5. Tesla Model Y body arrives as Giga Texas hinting at structural battery pack production – TeslaOwners Online

Leave a Comment