Characterization of the Thermal Properties of Electrochemical Energy Storage Devices and their Impact on Cell Degradation under High Pulsed Loading
Abstract
The likelihood of large-scale electrochemical energy storage, in the form of lithium-ion batteries, being integrated into future shipboard electrical power systems is fast increasing. This type of energy storage has potential to serve as both prime and intermediate power supplies for a wide host of electrical loads, both conventional and non-conventional. Among the many non-conventional loads that will be serviced are directed energy systems (DESs), which draw power at very high rates under unique pulsed profiles. When not used as the prime power supply for DESs, lithium-ion batteries may be used to buffer a large electrical generator whose power quality suffers when subjected to high intermediate loading. Though lithium-ion batteries have already found wide-scale deployment in many consumer electronic devices, the manner in which the Navy intends on operating them is vastly different requiring further research into how these cells perform, age, and fail under this type of high rate loading. It can be easily argued that the largest contributor to battery aging and failure stems from the high thermal load that is induced by both Ohmic and electrochemical phenomena, especially when they are cycled at high rates. Through previous work already supported by ONR, our groups have found that cylindrical lithium-ion batteries possess a high degree of thermal anisotropy, which makes cooling these devices incredibly challenging. This creates a high thermal gradient inside a cell, resulting in uneven aging throughout the jelly roll in the radial direction. With this in mind, there are still several system-level challenges associated with electrochemical storage and conversion using lithium-ion cells. It is proposed here that a deeper investigation into the thermal properties of lithium-ion batteries at the materials level will be carried out and validation of the impact of thermal stresses on cell degradation will be experimentally evaluated. Unique experimental and analytical tools are already in place to carry out the proposed research that will help develop a fundamental understanding of the thermal dynamics of Li-ion cells undergoing high rate pulsed charge and discharge. The proposed experimental and analytical modeling research is expected to result in an enhanced fundamental understanding of thermal issues in Li-ion cells, leading to tools and methodologies for the design and optimization of future energy conversion tools.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jun 10, 2016
- Source ID
- N000141612223
Entities
People
- David A. Wetz
Organizations
- Office of Naval Research
- United States Navy
- University of Texas at Arlington