High capacity polymer cathode and high energy density rechargeable cell comprising the cathode

Abstract

The invention features a rechargeable cathode and a battery comprising the cathode. The cathode includes a solid, ionically conducting polymer material and electroactive sulfur. The battery contains a lithium anode; the cathode; and an electrolyte; wherein at least one of anode, the cathode and the electrolyte, include the solid, ionically conducting polymer material.

Description

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT[0001]N / ABACKGROUND OF THE INVENTION[0002]Batteries have become increasingly important in modern society, both in powering a multitude of portable electronic devices, as well as being key components in new green technologies. These new technologies offer the promise of removing the dependence on current energy sources such as coal, petroleum products, and natural gas which contribute to the production of by-product green-house gases. Furthermore, the ability to store energy in both stationary and mobile applications is critical to the success of new energy sources, and is likely to sharply increase the demand for all sizes of advanced batteries. Especially for batteries for large applications, a low base cost of the battery will be key to the introduction and overall success of these applications.[0003]Conventional batteries have limitations, however. For example, lithium ion and other batteries generally employ a liquid...

AI Technical Summary

Benefits of technology

[0019]The solid, ionically conductive polymer material can also be useful as a separator film, as it is electrically non-conductive, and ionically conductive. Therefore the solid, ionically conductive polymer material cast or otherwise rendered as a film can be used as a separator positioned between an anode and cathode. In addition, the solid, ionically conductive polymer material can be coated onto an electrode to function as a separator or alternatively to isolate the electrode or an electrode component from another battery component such as an aqueous electrolyte. The solid, ionically conductive polymer material enables ionic communication between such an isolated component despite it being physically separated, and electrically segmented from the rest of the battery component. The material can also comprise an aggregated or cast agglomeration of small particles of the solid, ionically conductive polymer material. Such an aggregation can take any shape but include an engineered porosity while possessing an engineered surface area. Fillers, such as hydrophobic materials can be mixed in the material to provide desirable physical properties such as low effective aqueous porosity. Thus the solid, ionically conductive polymer material can include a low or very high surface area, and or a low or very high porosity. Shapes such as an annulus and other moldable shapes can be engineering with desired physical properties with the ionic conductivity of the solid, ionically conductive polymer material are enabled by the invention.

Problems solved by technology

Conventional batteries have limitations, however.

For example, lithium ion and other batteries generally employ a liquid electrolyte which is hazardous to humans and to the environment and which can be subject to fire or explosion.

Conventional liquid electrolyte suffers from the build-up of a solid interface layer at the electrode / electrolyte interface which causes eventual failure of the battery.

Conventional lithium ion batteries also exhibit slow charge times and suffer from a limited number of recharges since the chemical reaction within the battery reaches completion and limits the re-chargeability because of corrosion and dendrite formation.

While these methods have met with various degrees of success in limiting the polysulfide shuttle mechanism, they all rely on the use of expensive materials which are not well suited to large scale manufacturing.

Images