2021 BMW iX3

The 2021 BMW iX3 was the first electric vehicle off the BMW Gen5 battery system.

  • Total Energy = 80.3 kWh
    • Usable Energy = 74 kWh
    • SoC Window = 92.2%
  • Nominal Voltage = 345 V
    • Voltage Range = 394.8 V to 235 V
  • Configuration = 94s2p
    • Cell count = 188
  • Nominal Capacity = 232 Ah
  • Peak 10s Power = 233 kW

We see 10 modules with double stacking under the 2nd row seats. The HV distribution and BMS are all located on top of the rear modules. Cooling pipes run through the centre between the modules and all of the HV electrical connections are made on top of the modules.

The battery pack frame is constructed from extruded aluminium.

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

Charging

  • Fast Charge Power = 150 kW
  • 0-80% charge time = 34 minutes

With a cell DCIR of 0.87mΩ the joule heating for the fast charge from 0-80% would have a peak at 6.2kW and an average of 4.5kW a value that should easily be within the cooling capability of the heat pump.

Our calculations show that moving from a stepped fast charge limit to a continuous fast charge limit curve could improve the fast charge time by more than 1 minute 30 seconds.

Dimensions

  • Pack Mass = 518 kg (declared on pack label)
    • Cell Mass = 325 kg
    • Pack-Cells = 193 kg
    • Cell to Pack Ratio = 62.8 %

Thermal Control

  • Cooling = cooling plates on base of prismatic cells
  • Cooling medium = liquid
  • Heat pump

Pack Metrics

Warranty

  • 8 years
  • 100,000 miles

Cell

The cell is made by CATL and is a prismatic with an NMC811 cathode and a graphite anode. The jelly roll axis is along the longest axis of the cell case.

  • Made by CATL
  • Format = Prismatic
  • Chemistry = NMC811
  • Nominal Capacity = 116 Ah
  • Nominal Voltage = 3.67 V
  • Nominal Energy = 426 Wh
  • Dimensions = 301.7 x 26.5 x 91mm (94.7mm including terminals)
  • Cell Mass = 1.73 kg
  • Discharge
    • Peak 10s = 900A
    • Continuous = 450A
  • Charge
    • Peak = 400A
    • Continuous = 184A
  • DCIR (25°C, 50% SoC, 10s) = 0.87mΩ

The orientation of the jelly roll in this cell and the based cooling plates is not optimum as the thermal conductivity is much greater in the plane of the active materials.

References

  1. BMW iX3 Specifications
  2. BMW iX3, Electric Vehicle Database
  3. The first-ever BMW iX3, BMW Press

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