The first cradle-to-gate emissions assessment for a mass-produced, lithium-ion electric vehicle battery-pack has been created by researchers from Ford’s Research and Innovation Center and LG Chem’s Corporate R&D group.
The assessment relates to the lithium-ion battery pack used in the Ford Focus Electric. A new paper detailing the work has been published in the ACS journal Environmental Science & Technology.
To clarify the above wording, cradle-to-gate refers to the gate of the factory — meaning, that it takes into account the full manufacturing process right up to the point of shipment or delivery to consumers.
The researchers apparently based their assessment on the bill of materials and energy and materials input data from the battery cell and pack supplier (LG Chem). Green Car Congress notes that the researchers “calculated that the cradle-to-gate greenhouse gas emissions for the 24 kWh (kilowatt-hours) Ford Focus lithium-ion battery are 3.4 metric tonnes of CO2-eq (140 kg CO2-eq per kWh or 11 kg CO2-eq per kg of battery). Cell manufacturing is the key contributor accounting for 45% of the GHG emissions.”
When the system boundary is extended to include “the entire vehicle, they estimated a 39% increase in the cradle-to-gate GHG emissions of the Focus BEV compared to the Focus internal combustion engine vehicle (ICEV), which falls within the range of literature estimates of 27-63% increases for hypothetical non-production BEVs.”
To provide a bit more background on the battery pack in the Ford Focus EV — it’s composed of 430 different cells, possesses a nominal voltage of 3.7 V, and possesses a specific energy of 0.08 kWh/kg. The cells are provided by LG Chem, and the battery pack is put together by Piston Group in Michigan.
The paper provides more, comparing the total lifecycle emissions of the profiled EV and ICE vehicles:
Using our GHG estimate for BEV battery production, 11 kg CO2-eq/kg battery, in place of those in the literature gives an estimate of 31−37% life cycle GHG benefits for BEVs over gasoline ICEVs. Our results confirm the potential for BEVs to curb GHG emissions from the transportation sector. Current trends of increasing vehicle energy efficiency, decreasing burdens associated with battery production, decreasing burdens for electricity production, and increasing burdens for oil production are expected to increase the GHG emission benefits of electrification technology.
This roughly confirms most previous, related research. So, those of us who are fans of EVs, take heed.