Energy storage device having a current collector with inherent current limitations
Improvements in the structural components and physical characteristics of lithium battery articles are provided. Standard lithium ion batteries, for example, are prone to certain phenomena related to short circuiting and have experienced high temperature occurrences and ultimate firing as a result. Structural concerns with battery components have been found to contribute to such problems. Improvements provided herein include the utilization of thin metallized current collectors (aluminum and/or copper, as examples), high shrinkage rate materials, materials that become nonconductive upon exposure to high temperatures, and combinations thereof. Such improvements accord the ability to withstand certain imperfections (dendrites, unexpected electrical surges, etc.) within the target lithium battery through provision of ostensibly an internal fuse within the subject lithium batteries themselves that prevents undesirable high temperature results from short circuits. Battery articles and methods of use thereof including such improvements are also encompassed within this disclosure.
1. An energy storage device comprising an anode, a cathode, at least one separator present interposed between said anode and said cathode, at least one liquid electrolyte, and at least one current collector in contact with at least one of said anode and said cathode, wherein said at least one current collector has a top surface and a bottom surface; wherein said at least one separator is of a polymeric, ceramic, or nonwoven structure; wherein said at least one current collector is a nonconductive material having a conductive coating on both surfaces thereof; wherein said at least one current collector exhibits the capability to carry a current density when operating normally along a horizontal current pathway; and wherein said at least one current collector, when grounded and subjected to a current that is increased in 0.2 A increments through a polished 24 AWG copper wire in contact therewith, is unable to support a current of 20 A or more.
2. The energy storage device of claim 1 wherein said at least one liquid electrolyte is flammable.
3. The energy storage device of claim 2 wherein said at least one liquid electrolyte is an organic solvent.