2021 Lexus UX 300e Battery

The 2021 Lexus UX 300e battery has a total energy of 54.35kWh and is formed from 288 Panasonic prismatic cells.

A second tier of cells has been designed to fit under the 2nd row. This 2nd tier also appears to contain the BMS.

  • Usable energy = 45 kWh
  • Nominal Voltage = 355.2 V

The battery pack operates at a nominal 355.2V, the inverter contains a circuit that boosts and inverts the 355.2 Volts DC from the traction battery assembly to 500 Volts AC to power the motor [2].

  • Nominal Capacity = 153 Ah
  • Configuration = 96s 3p
    • 288 cells in total
  • Power = 167 kW10s

The power has been estimated based on 150kW motor power [1] and assuming a 90% efficiency, hence the battery pack needing to deliver 150 / 0.9 = 167kW peak.

  • Pack Mass = 415 kg
    • Cell Mass = 255 kg
    • Pack-Cells = 160 kg
    • Cell to Pack Ratio = 61.5 %
  • Cooling
    • closed loop refrigerated air

This post has been built based on the support and sponsorship from: About:EnergyAVANT Future MobilityQuarto Technical ServicesTAE Power Solutions and The Limiting Factor. 

In the image the air circulation fan and ducts are mirrored on both sides of the battery pack. Putting the air ducts into the outer crush space is sensible as they will compress easily and will not cause any electrical isolation risks.

The ducts bifurcate into an upper and lower branch to cool the second tier of modules.

Using re-circulated refrigerated air to cool a battery pack can be a good way of also removing humidity from the battery pack. However, the air temperature and flow does need to be carefully managed to minimise temperature deltas and to avoid cold areas on cells that could lead to lithium plating.

The 2021 Lexus UX 300e battery has been positioned to allow the front footwell to be slightly lower to improve the driving position.

There is significant structure in the battery frame to support the pack and provide both longitudinal and side impact crash protection.

The structural connections from the front of the vehicle into the battery pack appear to be very similar to a traditional ICE design. The rear end structure doesn’t show a clear connection into the battery pack in this view.


  • Make: Panasonic
    • Format = Prismatic
    • Capacity = 51 Ah
    • Nominal voltage = 3.7 V
    • Nominal energy = 188.7 Wh
    • Mass = 0.886 kg


  2. UX300e Electric Vehicle Dismantling Manual, Lexus Technical
  3. Lexus UX 300e Will Get 10 Year Battery Warranty, Lexus Enthusiast

2023 Lexus RZ 450e

The design of the pack is flat and rectangular with just 4 modules, this pack is as good as or better than the Tesla Mode 3 for simplicity.

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