The present invention relates generally to solid-state battery techniques. In particular, the present invention provides techniques for manufacturing a cathode, a catholyte, an electrolyte, or combination thereof, material having a desired ion conductivity. More particularly, the present invention provides an apparatus and method for the formation of a plurality of nanodimensioned particles with a selected composition that is useful for making cathode, catholyte, electrolyte, or combination thereof, materials to improve the ionic conductivity, for example, in a solid state battery. Merely by way of example, the invention has been applied to solid-state battery cells, although there can be other applications.
A high level of development has occurred in electronic and communication apparatuses. As an example, certain apparatus include, among others, a personal computer, a video camera and a portable telephone, commonly termed a “smart phone.” Examples of popular smart phones include the iPhone™ from Apple Inc. of Cupertino, Calif. or those phones using the Android™ operating system of Google Inc. in Mountain View, Calif. Other popular apparatus include electric or hybrid automobiles such as those from Tesla Motors Inc. in Fremont, Calif. or the Prius manufactured by Toyota Motor Corporation. Although highly successful, these popular apparatuses are limited by storage capacity and in particular battery capacity. A lithium battery has been presently noticed with regard to having a high energy density and with respect to various kinds of batteries. However, certain problems in the production of lithium batteries exist.
Liquid electrolytes containing a flammable organic solvents have been used for conventional lithium batteries. Unfortunately, lithium batteries often require a safety device for restraining a temperature rise in the battery which can be caused by a short circuit. A lithium battery configured with a solid electrolyte layer, which replaces the liquid electrolyte, has been described to improve the safety of lithium batteries and the devices which incorporate them. For example, a sulfide-based solid electrolyte material is known as a solid electrolyte material useful for a solid-state lithium battery.
Techniques for improving the production of solid-state batteries, as well as for the constituent components thereof, are still needed.
A challenge associated with the field to which the methods and systems described herein relate is the potentially slow mass transfer of lithium ions through a cathode active material having a metal halide or a lithium fluoride matrix, which may be in the form of particles. As a consequence, the full capacity of a battery incorporating these materials is not realized because many reactive sites are inaccessible in a period of time required for charging or discharging the battery in certain applications. Further, the rate performance of these material can be relatively poor given that the diffusion and migration time of lithium ions through the matrix takes long a time. Still further, a significant mass transport overpotential is associated with charging and discharging these materials. This overpotential results in lower energy delivered to the application, more heat generation, which can cause problems at a systems level, and lower efficiency, which increases the cost to the consumer. This challenge may also exist in batteries employing conversion materials with metal species other than iron, oxidizing species other than fluoride, and/or reducing cation species other than lithium ions.
To address the challenge of slow mass transport, the methods and apparatuses set forth herein provide, for example, for the manufacture of positive electrode nanodimensioned materials that contains elemental metal or an alloy thereof and a lithium compound (in the discharged state) or a metal compound (in the charged state) and which may be provided in the form of extremely small particles. In doing so, the methods, systems, and apparatuses set forth herein, surprisingly provide, inter alia, solutions to many of the aforementioned challenges.