2022 Nissan Ariya

The 2022 Nissan Ariya has two battery pack sizes, 63kWh (66kWh total) and 87kWh (91kWh total). The vehicle is also available in 2WD and 4WD variants.

The details around the battery specifications are very scarce and hence lots of gaps we need to gradually fill. However, I think this is worth sharing for the thermal and structural elements of the design.

Specifications:

Nissan have reduced the complexity by making the lower section of the two packs common. The extra energy in the larger battery pack is housed under the 2nd row passenger seats.

The mass delta between the 2WD vehicle with the 66kWh and 91kWh batteries = 180kg

The cooling system for the Ariya batteries is integrated into the aluminium extruded baseplate.

The flow channels being very well connected to the upper surface of the extrusion, with the module thermally bonded to the upper surface.

The cavity around the channel acting as some thermal isolation.

As the baseplate is extruded aluminium and this conducts heat very well, the isolation of the flow channels will not be that good. Hence the heat exchange with the environment is probably quite significant.

The coolant pipework for the battery temperature management system have casings, to enable individual control of temperature in each module. The recycling process for batteries will be similar to that of the LEAF.

Flowing the coolant down one half of the pack and then returning that back through the other half would impose a significant delta T. This could have been overcome to some extent by flow down and back in flow channels that were adjacent and then using the good conductivity of the aluminium to help reduce the delta T.

• cell make and model

Key Pack Metrics:

• Gravimetric energy density, pack = 150Wh/kg (66kWh) and 148Wh/kg (91kWh)
  • Cell =
• Volumetric energy density, pack =
• Gravimetric power density, pack =
• Volumetric power density, pack =
• Estimated cost = $/kWh
• Cell to Pack mass ratio =
  • module to pack mass ratio = %
• Cell to Pack volume ratio

Other key features:

• Safety
• BMS
• HV Distribution
• HV and LV Connections
• Cooling Connections
  • Front of pack and outside the battery volume
• Structural – a pack that has been integrated into the structure to enhance the structural performance of the vehicle:

To increase the height of the interior space, a holistic review of the underfloor structure was performed for battery storage. It was determined that the cross members be embedded in the structure such that the necessary battery capacity (explained later) is secured while providing temperature control system without compromising the strength and rigidity of the vehicle body (Fig. 2). The new structure enabled development of a body-integrated battery package with high rigidity, which allowed the mounting of an ultrathin large capacity battery. [1]

Furthermore, the torsional rigidity of the entire vehicle body was improved by connecting the high-rigidity package to the front and rear parts of the body. [1]

Also, the lateral stiffness of the suspension member fastening point was increased and steering responsiveness was improved. [1]

As there is no floor tunnel it makes packaging of front to rear services more complex:

• The water pipe for the rear motor passes through the side rail extrusion of the battery pack.
• The high-voltage wiring harness connected to the rear motor inverter was changed to a bus bar and rerouted within the high-voltage battery pack.
• The brake pipe was rerouted in the gap between the battery pack and side sill.

• Case material = extruded aluminium
• Sealing strategy
• Venting strategy
• Durability
• Warranty
• Availability
• Recycling
• Shipping

References

1. Technical Articles on all Aspects of the new Ariya EV – Nissan Technical Review
2. The New Nissan ARIYA: An Exclusive Interview With Nissan Chief Engineer Hikaru Nakajima, CleanTechnica