The Ferrari Elettrica has a 122kWh battery pack, 800V and cells made by SK On.
Metrics
- Gravimetric Energy Density
- Pack = 195 Wh/kg
- Cell = 305 Wh/kg
- Gravimetric Power Density
- Pack = 1282 W10s/kg
- Cell ~ 1580 W10s/kg
- Cell to Pack Mass Ratio = 63.9 %
Specifications
- Total energy
= 122 kWh - Nominal Voltage = 767.3 V
- Nominal Capacity = 159 Ah
- Peak Power ~ 802 kW10s
- Peak Current = 1200 A10s
- Regen Power = 500 kW10s
- Fast Charge Power = 350 kW
- Pack Mass ~ 625.6 kg
- Cell Mass ~ 400 kg
- Pack-Cells ~ 225.6 kg
- IP Rating = IP67
- Configuration = 210s 1p
- Total Cells = 210
Ferrari say quite a lot about the integration of the battery pack and the chassis. However, this appears to be a familiar design that has been used in Battery Electric Vehicles over the last 10-15 years.
The sealing flange is planar making for a more robust final seal. The double stack two rear modules sit under the bulge of the top cover and have a cooling plate underneath.
The above image shows a total of 16 bosses for the top-down fixings from the body into the battery pack. The perimeter fixings will then be bottom-up through the battery flange into the body.
This image shows just how close the modules are packaged down the centreline and that there is a plate fixed between the modules across the pack.
It isn’t clear how the tolerances work for this plate as the modules are also bolted vertically. Also, we don’t know if these plates are on each side of the modules.
There are no beams within the pack to support the crash performance of the body. Ferrari make the following point:
In the central part of the chassis, the battery is integrated completely into the chassis and situated under the floorpan of the car. This design solution helped minimise the overall weight of the battery/chassis system and places the battery pack in the lowest possible position in the vehicle. The chassis also serves a structural protection function for the battery pack, which is placed within the chassis itself, with spaces between the modules and the sills, to ensure that the energy is absorbed completely by the sills in case of a side-on impact.
Ferrari [2]
The aluminium siderails appear to be substantial with a number of fixing points to the body structure. The upright surround appears to have a cast aluminium plate where the external connections are made to cooling, electrical and comms and the sides appear to be a rolled and pressed aluminium (please do correct).
The fixing bosses for the rear 2 modules appear to be a feature bolted in place between the last 2 rows of modules.
For a very premium performance application this is a very repairable battery pack design.
Ferrari also explain how they have positioned the driver and front passenger to avoid the compromise of a front foot well feature that is seen in the Porsche Taycan battery.
The layout of the front seats is designed to accommodate the cells without sacrificing any space for the rear occupants and ensured the distribution of the cells without compromising the centre of gravity of the car. The driver’s seat was positioned further forwards also redefining the layout of the rear seats, which are more reclined, to offer even better on-board comfort.
Cooling
Liquid cooled pack that uses 3 cooling plates. Two plates cool the lower 13 modules and 1 plate is under the 2nd tier modules.
As there are 3 coolant plates and they sit within the pack enclosure it means there are coolant connections inside the battery pack.
The coolant plates have cut-outs where bosses for module fixings protrude through. These four fixings locate the modules and fix the pack into the floorpan of the body. A substantial mechanical integration. The turquoise Thermal Interface Material (TIM) is laid in a very clear repeated pattern.
Module
The battery pack consists of 15 modules. Each module containing 14 cells in a 14s 1p configuration.
This post has been built based on the support of and sponsorship from: Resonate Testing Ltd, Quarto Technical Services, Eatron Technologies and About:Energy
The image showing a module during assembly clearly shows the expansion pads between the cells.
The cast aluminium sideplates have a feature that locates the module top plate.
In the lower images the handed shared fixing points are clearly visible.
Image showing how the bosses on the modules overlap and bolts then locate the modules into the baseplate and from above through the body locate into the body structure.
Images showing the folded cell tabs welded to create a series string. This also shows the voltage measurement points for this end of the module.
Voltage measurements are also made at the opposite end of the module.
Cell
Specifications
The cell is made by SK On.
- Chemistry = NMC
- Format = Pouch
- Nominal Capacity = 159 Ah
- Nominal Voltage = 3.65 V
- Nominal Energy = 581 Wh
- Mass = 1.905 kg
Based on the declared peak pack current capability of 1200A and the fact that the cells are configured such that all are in series, the peak cell capability is 1200A.
Assuming this peak capability is at 50% SOC and that this peak current pulls the cell voltage down to a minimum 2.5V we can estimate the internal resistance of the cell (10s DCIR).
DCIR (10s at 50% SOC) ~ 0.96mΩ
Converting this into a conductance vs cell capacity (1.79 Siemens / Wh) allows us to scale the cell capability.
For a very premium performance application this is a very repairable battery pack design. Also in the literature [1,2] Ferrari state that this is designed to be upgradeable. A key aspect for a vehicle that is likely to be held in a vehicle collection for many 10’s of years.
References
- Ferrari Elettrica, Ferrari product page
- Ferrari Elettrica (pdf), Ferrari News
See also: Benchmarking Battery Packs, CATL