Formula E Battery Pack 2014-18

The Formula E battery pack 2014-18 was the first generation battery pack and was developed by Williams Advanced Engineering and supplied to every manufacturer in the series.

Specifications:

• total energy = 165 x 3.7V x 53Ah = 32,356Wh = 32kWh
• usable energy = maximum usable energy of 28 kWh
  • Usable SoC window = 87.5%
• peak discharge power kW_10s and kW_1s at %
  • 150kW peak race limit for season 1
  • 170kW peak race limit for season 2
  • 200 kW peak power limit
• continuous power = 90kW
• nominal voltage = 610 V
• capacity = 53Ah
• voltage range [V] = 446V to 693V
  • Cell 2.7V minimum to 4.2V maximum
  • 1000V maximum allowed bus voltage
• weight = 320kg
  • 200 kg (440 lb) cell-weight limit
    • Actual cell weight = 165 x 1.16kg = 191.4kg
    • (note that the cell mass varies between 1.095kg and 1.16kg depending on spec sheet)
• volume pack = (based on dimensions)
  • module =
• pack dimensions [m] =
  • module =
• number of cells [#] = 165
  • 165s
  • 1p
• charge time [minutes]
• cell format = Pouch
• modules
  • 5 modules, each with 33 cells
• cooling system
  • Cell cooling over the body of the pouch and the tabs
  • Patented thermal technology provides indirect cell liquid cooling
  • Coolant is dielectric (non electrical conducting)
  • Cooling system is to be used to pre and post condition the battery temperature
  • Both the pump and heat exchanger are external to the battery pack
• cell make and model
  • XALT 53Ah HE NMC SLPB120216216
• pack cost

Key Pack Metrics:

• Gravimetric energy density, pack = 101Wh/kg (pack gravimetric comparison)
  • Module = Wh/kg
  • Cell = 169Wh/kg (comparison of cell Wh/kg)
• Volumetric energy density, pack = Wh/litre
  • Module = Wh/litre
  • Cell = 319Wh/litre
• Gravimetric power density, pack = 625W/kg_10s
• Volumetric power density, pack = W/litre_10s
• Estimated cost $ to $ => ~$/kWh
• Cell to Pack mass ratio = 191.4 / 320 = 59.8%
  • module to pack mass ratio = %
• Cell to Pack volume ratio =

Also, these specifications and metrics can be cross-correlated to check their legitimacy.

Other key features:

• Safety
  • Passed FIA crash testing
  • WAE patented thermal protection and electrical isolation layer technology into the battery casing [2]
  • UN38.3 transport
  • On Track Safety Procedures
  • Crash Testing
  • Shock Testing

• BMS design
  • 15 CMUs individually monitoring Voltage, Cell Temp, etc
  • Individual Cell Voltage monitoring
  • Individual Cell Temperature monitoring
  • Isolation monitoring
  • Battery Current monitoring
  • HV Interlock System monitoring
  • Power Limit De-ratings
  • BMS has internal datalogger and will log all battery and cell data during the race day
• BMS broadcasts

• HV Distribution
  • Contactors
  • External “organ stops” can be pulled to isolate battery
• HV and LV Connections
• Cooling Connections
• Structure
  • The pack is a structural element of the car
  • Mechanical support of the cells updated to improve vibration robustness for 2017 [3]
• Case material
• Sealing strategy
• Venting strategy
  • Vents on underside of the pack
• Durability – % of pack capacity available after 10 years
  • Over four seasons, there have been only two on-track failures and the equivalent of more than 1,000 cars have raced using the battery since the championship started, representing a success rate of more than 99.5 percent. [1]
• Availability
• Recycling
• Shipping
  • Pack meets UN regulation 38.3 for the safe air transportation of lithium ion batteries

Also, if you have images of the battery that we can use to illustrate more of the design features then do let us know (editor). Or in fact if you have data on other packs that we can share on our benchmarking pages then do let us know.

References:

1. Formula E Batteries, Williams Advanced Engineering
2. Formula E, “THE FORMULA E BATTERY: Q&A WITH CRAIG WILSON”
3. ElectronicDesign, “Under the Hood of the EVs in the FIA Formula E Championship”
4. Formula E, “Welcome to the future. Welcome to Gen2.”
5. Worwood, D.; Marco, J.; Kellner, Q.; Hosseinzadeh, E.; McGlen, R.; Mullen, D.; Lynn, K.; Greenwood, D. Experimental Analysis of a Novel Cooling Material for Large Format Automotive Lithium-Ion Cells. Energies 2019, 12, 1251.

Formula E Battery 2019-21

This Gen 2 battery pack is nearly double the capacity. The gravimetric density increases from 625W/kg_10s to 649W/kg_10s.

Formula E

The Formula E series is designed to push the forefront of EV technology. Hence the specifications get more demanding each year and make a jump in design at each generation. There are now two battery packs that we have explored in detail and a third on the horizon.

This is our Battery Pack Benchmarks and hence we would like to understand if this is useful and how we could improve it. Also, if you have material that could be added to improve it or we should link to.