Polymer electrolyte, intercalation compounds and electrodes for batteries

Abstract

Solid battery components are provided. A block copolymeric electrolyte is non-crosslinked and non-glassy through the entire range of typical battery service temperatures, that is, through the entire range of at least from about 0° C. to about 70° C. The chains of which the copolymer is made each include at least one ionically-conductive block and at least one second block immiscible with the ionically-conductive block. The chains form an amorphous association and are arranged in an ordered nanostructure including a continuous matrix of amorphous ionically-conductive domains and amorphous second domains that are immiscible with the ionically-conductive domains. A compound is provided that has a formula of LixMyNzO2. M and N are each metal atoms or a main group elements, and x, y and z are each numbers from about 0 to about 1. y and z are chosen such that a formal charge on the MyNz portion of the compound is (4-x). In certain embodiments, these compounds are used in the cathodes of rechargeable batteries. The present invention also includes methods of predicting the potential utility of metal dichalgogenide compounds for use in lithium intercalation compounds. It also provides methods for processing lithium intercalation oxides with the structure and compositional homogeneity necessary to realize the increased formation energies of said compounds. An article is made of a dimensionally-stable, interpenetrating microstructure of a first phase including a first component and a second phase, immiscible with the first phase, including a second component. The first and second phases define interphase boundaries between them, and at least one particle is positioned between a first phase and a second phase at an interphase boundary. When the first and second phases are electronically-conductive and ionically-conductive polymers, respectively, and the particles are ion host particles, the arrangement is an electrode of a battery.

Description

RELATED APPLICATIONS [0001] This is a continuation application of U.S. patent application Ser. No. 09 / 862,916, filed May 22, 2001, which is a divisional of U.S. patent application Ser. No. 09 / 284,447, filed Jun. 24, 1999 which is a national stage of and claims priority to International Application No. PCT / US97 / 18839 filed Oct. 10, 1997, which claims priority to U.S. Provisional Application No. 60 / 028,342, filed Oct. 11, 1996; U.S. Provisional Application No. 60 / 028,341, filed Oct. 11, 1996; U.S. Provisional Application No. 60 / 028,278, filed Oct. 11, 1996; and U.S. Provisional Application No. 60 / 053,876, filed Jul. 28, 1997.[0002] This invention was made with government support under Contract Number DEFC07-941D13223 awarded by the U.S. Department of Energy and Grant Number NIH-5P30-ES02109 awarded by the National Institutes of Health. The government has certain rights in the invention.FIELD OF THE INVENTION [0003] The present invention relates generally to batteries, and more particu...

AI Technical Summary

Benefits of technology

The present invention provides improved ion host particles, electrodes, and electrolytes for lithium batteries. These improvements can be used separately or in combination with each other to create better performing batteries. The invention also provides a method for making the improved components. Overall, the invention provides a more efficient and effective way to create batteries with better performance and longer lifespan.

Problems solved by technology

For example, LixCoO2, LixV3O13 and LixTiS2 are relatively expensive to prepare.

Moreover, LixNiO2 is comparatively difficult to process.

Furthermore, LixMn2O4 possesses a limited capacity for providing energy.

While the above and other reports represent, in some cases, interesting lithium compounds for electrochemical devices, on the whole the prior art is directed towards relatively high-temperature firing of compounds resulting in generally low-energy state products.

Hence, it remains a challenge in the art to provide dichalcogenide compounds for use as lithium intercalation compounds that are relatively light-weight, inexpensive and easy to process and that have comparatively large formation energies.

Development of commercially-viable lithium solid polymer electrolyte batteries has been hindered by complications, in particular complications involving the electrolyte.

Dimensional stability can be achieved by crosslinking, crystallization, glassification, or the like, but these arrangements generally impede ionic conductivity since conductivity requires a significant degree of polymer chain mobility.

For example, in linear chain polyethylene oxide (PEO) lithium salt electrolytes, crystallinity can severely hinder the mobility of the polymer chains, compromising room temperature ionic conductivities.

However, these strategies generally have yielded materials with poor mechanical properties, i.e., materials that behave more like liquids than solids since, as crystallinity in PEO is reduced via these techniques, dimensional stability necessary for application in solid state batteries is compromised.

The ionic conductivity of crosslinked systems is, however, inherently hindered by the presence of the crosslinks, as the crosslinks suppress chain mobility.

Additionally, crosslinked materials tend to be non-recyclable.

In typical prior art arrangements, however, expansion and contraction of the mixture of particles occurring naturally during the course of charging and discharging, and due to temperature change of the environment in which the cathode is used, can result in loss of inter-particle contact, in particular, disconnection of the lithium host particle / electronically conductive particle interface.

Moreover, repeated cycling often results in increased electrical resistance within the cathode due to passivation of the intercalation compound surface.

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