Science Inventory

Effect of Current and SOC on Round-Trip Energy Efficiency of a Lithium-Iron Phosphate (LiFePO4) Battery Pack (SAE Paper 2015-01-1186)

Citation:

SAFOUTIN, M., J. CHERRY, AND J. MCDONALD. Effect of Current and SOC on Round-Trip Energy Efficiency of a Lithium-Iron Phosphate (LiFePO4) Battery Pack (SAE Paper 2015-01-1186). In Proceedings, 2015 SAE World Congress, Detroit, MI, April 21 - 23, 2015. SAE International, Warrendale, PA, SAE #2015-01-1186, (2015).

Impact/Purpose:

Roundtrip energy efficiency of a 22.8-kWh A123 Li-ion (Lithium Iron Phosphate, LiFePO4) battery pack was measured by adding and removing a fixed quantity of charge at currents between 0.2C and 2C and at SOCs between 10% and 90% at an average temperature of 25C.

Description:

While equivalent circuit modeling is an effective way to model the performance and energy efficiency of automotive Li-ion batteries, in some applications it is more convenient to refer directly to round-trip energy efficiency. Energy efficiency of either cells or full packs is seldom documented by manufacturers in enough detail to provide an accurate impression of this metric over a range of operating conditions. The energy efficiency of a full battery pack may also be subject to more variables than would be represented by extrapolating results obtained from a single cell, and can be more demanding to measure in an accurate and consistent manner. Roundtrip energy efficiency of a 22.8-kWh A123 Li-ion (Lithium Iron Phosphate, LiFePO4) battery pack was measured by adding and removing a fixed quantity of charge at currents between 0.2C and 2C and at SOCs between 10% and 90% at an average temperature of 25C.

Record Details:

Record Type: DOCUMENT (PAPER IN NON-EPA PROCEEDINGS)
Product Published Date: 04/14/2015
Record Last Revised: 09/14/2015
OMB Category: Other
Record ID: 288796

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF AIR AND RADIATION

OFFICE OF TRANSPORTATION AND AIR QUALITY

ADVANCED TECHNOLOGY DIVISION