Safety Evaluation of Lithium-ion Batteries Under Combined Mechanical and Electrical Abuse Conditions
Abstract
Safety Evaluation of Lithium-ion Batteries Under Combined Mechanical and Electrical Abuse ConditionsThe goal of the proposed research is to develop an experimental and modeling program to understand thecomplex and interactive effects of combined mechanical and" electrical loading on safety and integrity oflithium-ion cells, modules, and battery packs.Lithium-ion batteries are a favorable"" power source for various Navy applications because of their highenergydensity over their weight or volume. However, there is an in"herent risk in use of such batteries incase of inadvertent mechanical or electrical abuse. The Technical Manual for Navy Lithium Ba"ttery SafetyProgram Responsibilities and Procedures provides safety guidelines on design, testing, packaging, andtransportation of" lithium-ion batteries[1]. The packaging guideline is to reduce ~shock and vibration duringtransit to a minimum and prevents crushing among cells/batteries.~ the NAVSEA High-Energy StorageSystem Safety Manual[2] also emphasizes the importance of hazard analysis" in case of various modes ofabuse including mechanical and electrical abuses. Therefore, it is imperative to understand the respons"e oflithium-ion batteries in case of extreme loading conditions such as impact or explosive loading.Extensive studies on mechanical abuse of lithium-ion batteries by Sahraei and co-workers[3~8] shows thatbattery cells may go under limited crush without any detectable change in voltage until reaching a criticaldisplacement/force level that initiates internal short circuit. What has not been studied is probability offailure for a battery cell that has been subjected to an impact or crush but has not reached short circui"t, whenit is used in regular charge and discharge cycles. A small local deformation to a cell which does not createan instantaneou""s loss in voltage or failure may remain undetected, but create a change in internal resistanceof the cell and its charge and discha""rge profile. If this cell is used in a battery pack, this in turn may resultin non-uniform state of charge among the cells and trig"ger a failure. A local deformation in a cell may alsochange its tolerance to electrical abuse such as over current/voltage.Studies on combined effects of mechanical abuse with electrical loading do not exist in the current literatureand may provide a clue to se"veral unexplained failures of lithium-ion batteries in the field. It is often notpossible to find the root cause of battery fires," as the failed part is burned and disintegrated during thethermal runaway event. For example the Boeing Dreamliner or Samsung Note battery fires are stillremained with no definite explanation of the cause of the catastrophe. An understanding of the failure causesthrough well-planned experimental study and predictive modeling will provide a tool to improve the designof equipment to survive abusive conditions and prevent catastrophic failures from happening in the future.A comprehensive set of tests at cell level will be used to characterize the response of a single cell in caseof combined mechanical and electrical loading. Test results will be t"hen used to calibrate mechanical,thermal and electrical models of the cell. The models of compromised cells will then be combined w"ithmodels of fresh intact cells in a module arrangement to predict the effects of a local damage on the overallfunctioning and possibility of failure at module level. Additional tests on stack of cells will then be used tovalidate the module models. The module models will in turn be connected to predict the response at batterypack level.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Sep 29, 2017
- Source ID
- N000141712869
Entities
People
- Elham Sahraei Esfahani
Organizations
- George Mason University
- Office of Naval Research
- United States Navy